diff --git a/.ci/azure-buildtest-awkward.yml b/.ci/azure-buildtest-awkward.yml
index 4d3688e3aa..3f763f9a00 100644
--- a/.ci/azure-buildtest-awkward.yml
+++ b/.ci/azure-buildtest-awkward.yml
@@ -28,11 +28,11 @@ jobs:
         "py27-32bit":
           python.version: "2.7"
           python.architecture: "x86"
-          numpy.version: "latest"
+          numpy.version: "1.16.5"
         "py27-64bit":
           python.version: "2.7"
           python.architecture: "x64"
-          numpy.version: "latest"
+          numpy.version: "1.16.5"
         "py35-32bit":
           python.version: "3.5"
           python.architecture: "x86"
@@ -57,6 +57,14 @@ jobs:
           python.version: "3.7"
           python.architecture: "x64"
           numpy.version: "latest"
+        "py38-32bit":
+          python.version: "3.8"
+          python.architecture: "x86"
+          numpy.version: "latest"
+        "py38-64bit":
+          python.version: "3.8"
+          python.architecture: "x64"
+          numpy.version: "latest"
 
     steps:
       - checkout: self
@@ -90,11 +98,7 @@ jobs:
         "py27":
           python.version: "2.7"
           python.architecture: "x64"
-          numpy.version: "latest"
-        "py34":
-          python.version: "3.4"
-          python.architecture: "x64"
-          numpy.version: "latest"
+          numpy.version: "1.16.5"
         "py35":
           python.version: "3.5"
           python.architecture: "x64"
@@ -107,6 +111,10 @@ jobs:
           python.version: "3.7"
           python.architecture: "x64"
           numpy.version: "latest"
+        "py38":
+          python.version: "3.8"
+          python.architecture: "x64"
+          numpy.version: "latest"
 
     steps:
       - checkout: self
@@ -141,18 +149,18 @@ jobs:
           python.version: "2.7"
           python.architecture: "x64"
           numpy.version: "1.13.1"
-        "py27-np*":
+        "py27-np16":
           python.version: "2.7"
           python.architecture: "x64"
-          numpy.version: "latest"
+          numpy.version: "1.16.5"
         "py34-np13":
           python.version: "3.4"
           python.architecture: "x64"
           numpy.version: "1.13.1"
-        "py34-np*":
+        "py34-np16":
           python.version: "3.4"
           python.architecture: "x64"
-          numpy.version: "latest"
+          numpy.version: "1.16.5"
         "py35-np13":
           python.version: "3.5"
           python.architecture: "x64"
@@ -177,6 +185,10 @@ jobs:
           python.version: "3.7"
           python.architecture: "x64"
           numpy.version: "latest"
+        "py38-np*":
+          python.version: "3.8"
+          python.architecture: "x64"
+          numpy.version: "latest"
 
     steps:
       - checkout: self
diff --git a/.ci/azure-deploy-awkward.yml b/.ci/azure-deploy-awkward.yml
index 7ff43aa703..daaecc3f01 100644
--- a/.ci/azure-deploy-awkward.yml
+++ b/.ci/azure-deploy-awkward.yml
@@ -72,11 +72,11 @@ jobs:
         "py27-32bit":
           python.version: "2.7"
           python.architecture: "x86"
-          numpy.version: "latest"
+          numpy.version: "1.16.5"
         "py27-64bit":
           python.version: "2.7"
           python.architecture: "x64"
-          numpy.version: "latest"
+          numpy.version: "1.16.5"
         "py35-32bit":
           python.version: "3.5"
           python.architecture: "x86"
@@ -101,6 +101,14 @@ jobs:
           python.version: "3.7"
           python.architecture: "x64"
           numpy.version: "latest"
+        "py38-32bit":
+          python.version: "3.8"
+          python.architecture: "x86"
+          numpy.version: "latest"
+        "py38-64bit":
+          python.version: "3.8"
+          python.architecture: "x64"
+          numpy.version: "latest"
 
     steps:
       - checkout: self
@@ -150,6 +158,10 @@ jobs:
           python.version: "3.7"
           python.architecture: "x64"
           numpy.version: "latest"
+        "py38":
+          python.version: "3.8"
+          python.architecture: "x64"
+          numpy.version: "latest"
 
     steps:
       - checkout: self
@@ -164,13 +176,16 @@ jobs:
       - script: |
           case $(python.version) in
           2.7)
-            FULL_VERSION=2.7.16
+            FULL_VERSION=2.7.17
             ;;
           3.6)
-            FULL_VERSION=3.6.8
+            FULL_VERSION=3.6.9
             ;;
           3.7)
-            FULL_VERSION=3.7.3
+            FULL_VERSION=3.7.5
+            ;;
+          3.8)
+            FULL_VERSION=3.8.0
             ;;
           esac
 
diff --git a/VERSION_INFO b/VERSION_INFO
index d8a023ec10..baa9837854 100644
--- a/VERSION_INFO
+++ b/VERSION_INFO
@@ -1 +1 @@
-0.1.19
+0.1.20
diff --git a/awkward1/_numba/array/listarray.py b/awkward1/_numba/array/listarray.py
index 2056d47b61..7524765c0a 100644
--- a/awkward1/_numba/array/listarray.py
+++ b/awkward1/_numba/array/listarray.py
@@ -11,6 +11,7 @@
 from ..._numba import cpu, util, content
 
 @numba.extending.typeof_impl.register(awkward1.layout.ListArray32)
+@numba.extending.typeof_impl.register(awkward1.layout.ListArrayU32)
 @numba.extending.typeof_impl.register(awkward1.layout.ListArray64)
 def typeof(val, c):
     return ListArrayType(numba.typeof(numpy.asarray(val.starts)), numba.typeof(numpy.asarray(val.stops)), numba.typeof(val.content), numba.typeof(val.id))
@@ -18,7 +19,7 @@ def typeof(val, c):
 class ListArrayType(content.ContentType):
     def __init__(self, startstpe, stopstpe, contenttpe, idtpe):
         assert startstpe == stopstpe
-        super(ListArrayType, self).__init__(name="ListArray{}Type({}, id={})".format(startstpe.dtype.bitwidth, contenttpe.name, idtpe.name))
+        super(ListArrayType, self).__init__(name="ListArray{}{}Type({}, id={})".format("" if startstpe.dtype.signed else "U", startstpe.dtype.bitwidth, contenttpe.name, idtpe.name))
         self.startstpe = startstpe
         self.contenttpe = contenttpe
         self.idtpe = idtpe
@@ -31,6 +32,10 @@ def stopstpe(self):
     def bitwidth(self):
         return self.startstpe.dtype.bitwidth
 
+    @property
+    def indexname(self):
+        return ("" if self.startstpe.dtype.signed else "U") + str(self.startstpe.dtype.bitwidth)
+
     @property
     def ndim(self):
         return 1 + self.contenttpe.ndim
@@ -58,7 +63,7 @@ def getitem_next(self, wheretpe, isadvanced):
 
         elif isinstance(headtpe, numba.types.SliceType):
             contenttpe = self.contenttpe.carry().getitem_next(tailtpe, isadvanced)
-            return awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(self.bitwidth), contenttpe, self.idtpe)
+            return awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(self.indexname), contenttpe, self.idtpe)
 
         elif isinstance(headtpe, numba.types.EllipsisType):
             raise NotImplementedError("ellipsis")
@@ -71,7 +76,7 @@ def getitem_next(self, wheretpe, isadvanced):
                 raise NotImplementedError("array.ndim != 1")
             contenttpe = self.contenttpe.carry().getitem_next(tailtpe, True)
             if not isadvanced:
-                return awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(self.bitwidth), contenttpe, self.idtpe)
+                return awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(self.indexname), contenttpe, self.idtpe)
             else:
                 return contenttpe
 
@@ -138,14 +143,17 @@ def unbox(tpe, obj, c):
 
 @numba.extending.box(ListArrayType)
 def box(tpe, val, c):
-    if tpe.bitwidth == 32:
-        Index_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.Index32))
-        ListArray_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.ListArray32))
-    elif tpe.bitwidth == 64:
+    if tpe.indexname == "64":
         Index_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.Index64))
         ListArray_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.ListArray64))
+    elif tpe.indexname == "32":
+        Index_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.Index32))
+        ListArray_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.ListArray32))
+    elif tpe.indexname == "U32":
+        Index_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.IndexU32))
+        ListArray_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.ListArrayU32))
     else:
-        raise AssertionError("unrecognized bitwidth")
+        raise AssertionError("unrecognized index type: {}".format(tpe.indexname))
     proxyin = numba.cgutils.create_struct_proxy(tpe)(c.context, c.builder, value=val)
     startsarray_obj = c.pyapi.from_native_value(tpe.startstpe, proxyin.starts, c.env_manager)
     stopsarray_obj = c.pyapi.from_native_value(tpe.stopstpe, proxyin.stops, c.env_manager)
@@ -258,12 +266,14 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
 
     if isinstance(headtpe, numba.types.Integer):
         assert advanced is None
-        if arraytpe.bitwidth == 64:
+        if arraytpe.indexname == "64":
             kernel = cpu.kernels.awkward_listarray64_getitem_next_at_64
-        elif arraytpe.bitwidth == 32:
+        elif arraytpe.indexname == "32":
             kernel = cpu.kernels.awkward_listarray32_getitem_next_at_64
+        elif arraytpe.indexname == "U32":
+            kernel = cpu.kernels.awkward_listarrayU32_getitem_next_at_64
         else:
-            raise AssertionError("unrecognized bitwidth")
+            raise AssertionError("unrecognized index type: {}".format(arraytpe.indexname))
 
         nextcarry = util.newindex64(context, builder, numba.int64, lenstarts)
         util.call(context, builder, kernel,
@@ -282,18 +292,23 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
     elif isinstance(headtpe, numba.types.SliceType):
         proxyslicein = numba.cgutils.create_struct_proxy(headtpe)(context, builder, value=headval)
 
-        if arraytpe.bitwidth == 64:
+        if arraytpe.indexname == "64":
             determine_carrylength = cpu.kernels.awkward_listarray64_getitem_next_range_carrylength
             fill_carry = cpu.kernels.awkward_listarray64_getitem_next_range_64
             determine_total = cpu.kernels.awkward_listarray64_getitem_next_range_counts_64
             fill_nextadvanced = cpu.kernels.awkward_listarray64_getitem_next_range_spreadadvanced_64
-        elif arraytpe.bitwidth == 32:
+        elif arraytpe.indexname == "32":
             determine_carrylength = cpu.kernels.awkward_listarray32_getitem_next_range_carrylength
             fill_carry = cpu.kernels.awkward_listarray32_getitem_next_range_64
             determine_total = cpu.kernels.awkward_listarray32_getitem_next_range_counts_64
             fill_nextadvanced = cpu.kernels.awkward_listarray32_getitem_next_range_spreadadvanced_64
+        elif arraytpe.indexname == "U32":
+            determine_carrylength = cpu.kernels.awkward_listarrayU32_getitem_next_range_carrylength
+            fill_carry = cpu.kernels.awkward_listarrayU32_getitem_next_range_64
+            determine_total = cpu.kernels.awkward_listarrayU32_getitem_next_range_counts_64
+            fill_nextadvanced = cpu.kernels.awkward_listarrayU32_getitem_next_range_spreadadvanced_64
         else:
-            raise AssertionError("unrecognized bitwidth")
+            raise AssertionError("unrecognized index type: {}".format(arraytpe.indexname))
 
         carrylength = numba.cgutils.alloca_once(builder, context.get_value_type(numba.int64))
         util.call(context, builder, determine_carrylength,
@@ -308,10 +323,10 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
              util.cast(context, builder, numba.intp, numba.int64, proxyslicein.step)),
             "in {}, indexing error".format(arraytpe.shortname))
 
-        nextoffsets = util.newindex(arraytpe.bitwidth, context, builder, numba.int64, builder.add(lenstarts, context.get_constant(numba.int64, 1)))
+        nextoffsets = util.newindex(arraytpe.indexname, context, builder, numba.int64, builder.add(lenstarts, context.get_constant(numba.int64, 1)))
         nextcarry = util.newindex64(context, builder, numba.int64, builder.load(carrylength))
         util.call(context, builder, fill_carry,
-            (util.arrayptr(context, builder, util.indextpe(arraytpe.bitwidth), nextoffsets),
+            (util.arrayptr(context, builder, util.indextpe(arraytpe.indexname), nextoffsets),
              util.arrayptr(context, builder, util.index64tpe, nextcarry),
              util.arrayptr(context, builder, arraytpe.startstpe, proxyin.starts),
              util.arrayptr(context, builder, arraytpe.stopstpe, proxyin.stops),
@@ -334,7 +349,7 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
             total = numba.cgutils.alloca_once(builder, context.get_value_type(numba.int64))
             util.call(context, builder, determine_total,
                 (total,
-                 util.arrayptr(context, builder, util.indextpe(arraytpe.bitwidth), nextoffsets),
+                 util.arrayptr(context, builder, util.indextpe(arraytpe.indexname), nextoffsets),
                  lenstarts),
                 "in {}, indexing error".format(arraytpe.shortname))
 
@@ -342,14 +357,14 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
             util.call(context, builder, fill_nextadvanced,
                 (util.arrayptr(context, builder, util.index64tpe, nextadvanced),
                  util.arrayptr(context, builder, util.index64tpe, advanced),
-                 util.arrayptr(context, builder, util.indextpe(arraytpe.bitwidth), nextoffsets),
+                 util.arrayptr(context, builder, util.indextpe(arraytpe.indexname), nextoffsets),
                  lenstarts),
                 "in {}, indexing error".format(arraytpe.shortname))
 
             outcontenttpe = nextcontenttpe.getitem_next(tailtpe, True)
             outcontentval = nextcontenttpe.lower_getitem_next(context, builder, nextcontenttpe, tailtpe, nextcontentval, tailval, nextadvanced)
 
-        outtpe = awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(arraytpe.bitwidth), outcontenttpe, arraytpe.idtpe)
+        outtpe = awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(arraytpe.indexname), outcontenttpe, arraytpe.idtpe)
         proxyout = numba.cgutils.create_struct_proxy(outtpe)(context, builder)
         proxyout.offsets = nextoffsets
         proxyout.content = outcontentval
@@ -371,21 +386,23 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
         lenflathead = util.arraylen(context, builder, util.index64tpe, flathead, totpe=numba.int64)
 
         if advanced is None:
-            if arraytpe.bitwidth == 64:
+            if arraytpe.indexname == "64":
                 kernel = cpu.kernels.awkward_listarray64_getitem_next_array_64
-            elif arraytpe.bitwidth == 32:
+            elif arraytpe.indexname == "32":
                 kernel = cpu.kernels.awkward_listarray32_getitem_next_array_64
+            elif arraytpe.indexname == "U32":
+                kernel = cpu.kernels.awkward_listarrayU32_getitem_next_array_64
             else:
-                raise AssertionError("unrecognized bitwidth")
+                raise AssertionError("unrecognized index type: {}".format(arraytpe.indexname))
 
             lencarry = builder.mul(lenstarts, lenflathead)
             lenoffsets = builder.add(lenstarts, context.get_constant(numba.int64, 1))
 
             nextcarry = util.newindex64(context, builder, numba.int64, lencarry)
             nextadvanced = util.newindex64(context, builder, numba.int64, lencarry)
-            nextoffsets = util.newindex(arraytpe.bitwidth, context, builder, numba.int64, lenoffsets)
+            nextoffsets = util.newindex(arraytpe.indexname, context, builder, numba.int64, lenoffsets)
             util.call(context, builder, kernel,
-                (util.arrayptr(context, builder, util.indextpe(arraytpe.bitwidth), nextoffsets),
+                (util.arrayptr(context, builder, util.indextpe(arraytpe.indexname), nextoffsets),
                  util.arrayptr(context, builder, util.index64tpe, nextcarry),
                  util.arrayptr(context, builder, util.index64tpe, nextadvanced),
                  util.arrayptr(context, builder, arraytpe.startstpe, proxyin.starts),
@@ -404,7 +421,7 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
             contenttpe = nexttpe.getitem_next(tailtpe, True)
             contentval = nexttpe.lower_getitem_next(context, builder, nexttpe, tailtpe, nextval, tailval, nextadvanced)
 
-            outtpe = awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(arraytpe.bitwidth), contenttpe, arraytpe.idtpe)
+            outtpe = awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(arraytpe.indexname), contenttpe, arraytpe.idtpe)
             proxyout = numba.cgutils.create_struct_proxy(outtpe)(context, builder)
             proxyout.offsets = nextoffsets
             proxyout.content = contentval
@@ -413,12 +430,14 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
             return proxyout._getvalue()
 
         else:
-            if arraytpe.bitwidth == 64:
+            if arraytpe.indexname == "64":
                 kernel = cpu.kernels.awkward_listarray64_getitem_next_array_advanced_64
-            elif arraytpe.bitwidth == 32:
+            elif arraytpe.indexname == "32":
                 kernel = cpu.kernels.awkward_listarray32_getitem_next_array_advanced_64
+            elif arraytpe.indexname == "U32":
+                kernel = cpu.kernels.awkward_listarrayU32_getitem_next_array_advanced_64
             else:
-                raise AssertionError("unrecognized bitwidth")
+                raise AssertionError("unrecognized index type: {}".format(arraytpe.indexname))
 
             nextcarry = util.newindex64(context, builder, numba.int64, lenstarts)
             nextadvanced = util.newindex64(context, builder, numba.int64, lenstarts)
diff --git a/awkward1/_numba/array/listoffsetarray.py b/awkward1/_numba/array/listoffsetarray.py
index e6c3098f94..745bbfe50b 100644
--- a/awkward1/_numba/array/listoffsetarray.py
+++ b/awkward1/_numba/array/listoffsetarray.py
@@ -10,13 +10,14 @@
 from ..._numba import cpu, util, content
 
 @numba.extending.typeof_impl.register(awkward1.layout.ListOffsetArray32)
+@numba.extending.typeof_impl.register(awkward1.layout.ListOffsetArrayU32)
 @numba.extending.typeof_impl.register(awkward1.layout.ListOffsetArray64)
 def typeof(val, c):
     return ListOffsetArrayType(numba.typeof(numpy.asarray(val.offsets)), numba.typeof(val.content), numba.typeof(val.id))
 
 class ListOffsetArrayType(content.ContentType):
     def __init__(self, offsetstpe, contenttpe, idtpe):
-        super(ListOffsetArrayType, self).__init__(name="ListOffsetArray{}Type({}, id={})".format(offsetstpe.dtype.bitwidth, contenttpe.name, idtpe.name))
+        super(ListOffsetArrayType, self).__init__(name="ListOffsetArray{}{}Type({}, id={})".format("" if offsetstpe.dtype.signed else "U", offsetstpe.dtype.bitwidth, contenttpe.name, idtpe.name))
         self.offsetstpe = offsetstpe
         self.contenttpe = contenttpe
         self.idtpe = idtpe
@@ -25,6 +26,10 @@ def __init__(self, offsetstpe, contenttpe, idtpe):
     def bitwidth(self):
         return self.offsetstpe.dtype.bitwidth
 
+    @property
+    def indexname(self):
+        return ("" if self.offsetstpe.dtype.signed else "U") + str(self.offsetstpe.dtype.bitwidth)
+
     @property
     def ndim(self):
         return 1 + self.contenttpe.ndim
@@ -52,7 +57,7 @@ def getitem_next(self, wheretpe, isadvanced):
 
         elif isinstance(headtpe, numba.types.SliceType):
             contenttpe = self.contenttpe.carry().getitem_next(tailtpe, isadvanced)
-            return ListOffsetArrayType(util.indextpe(self.bitwidth), contenttpe, self.idtpe)
+            return ListOffsetArrayType(util.indextpe(self.indexname), contenttpe, self.idtpe)
 
         elif isinstance(headtpe, numba.types.EllipsisType):
             raise NotImplementedError("ellipsis")
@@ -65,7 +70,7 @@ def getitem_next(self, wheretpe, isadvanced):
                 raise NotImplementedError("array.ndim != 1")
             contenttpe = self.contenttpe.carry().getitem_next(tailtpe, True)
             if not isadvanced:
-                return ListOffsetArrayType(util.indextpe(self.bitwidth), contenttpe, self.idtpe)
+                return ListOffsetArrayType(util.indextpe(self.indexname), contenttpe, self.idtpe)
             else:
                 return contenttpe
 
@@ -127,14 +132,17 @@ def unbox(tpe, obj, c):
 
 @numba.extending.box(ListOffsetArrayType)
 def box(tpe, val, c):
-    if tpe.bitwidth == 32:
-        Index_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.Index32))
-        ListOffsetArray_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.ListOffsetArray32))
-    elif tpe.bitwidth == 64:
+    if tpe.indexname == "64":
         Index_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.Index64))
         ListOffsetArray_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.ListOffsetArray64))
+    elif tpe.indexname == "32":
+        Index_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.Index32))
+        ListOffsetArray_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.ListOffsetArray32))
+    elif tpe.indexname == "U32":
+        Index_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.IndexU32))
+        ListOffsetArray_obj = c.pyapi.unserialize(c.pyapi.serialize_object(awkward1.layout.ListOffsetArrayU32))
     else:
-        raise AssertionError("unrecognized bitwidth")
+        raise AssertionError("unrecognized index type: {}".format(tpe.indexname))
     proxyin = numba.cgutils.create_struct_proxy(tpe)(c.context, c.builder, value=val)
     offsetsarray_obj = c.pyapi.from_native_value(tpe.offsetstpe, proxyin.offsets, c.env_manager)
     content_obj = c.pyapi.from_native_value(tpe.contenttpe, proxyin.content, c.env_manager)
@@ -270,12 +278,14 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
 
     if isinstance(headtpe, numba.types.Integer):
         assert advanced is None
-        if arraytpe.bitwidth == 64:
+        if arraytpe.indexname == "64":
             kernel = cpu.kernels.awkward_listarray64_getitem_next_at_64
-        elif arraytpe.bitwidth == 32:
+        elif arraytpe.indexname == "32":
             kernel = cpu.kernels.awkward_listarray32_getitem_next_at_64
+        elif arraytpe.indexname == "U32":
+            kernel = cpu.kernels.awkward_listarrayU32_getitem_next_at_64
         else:
-            raise AssertionError("unrecognized bitwidth")
+            raise AssertionError("unrecognized index type: {}".format(arraytpe.indexname))
 
         nextcarry = util.newindex64(context, builder, numba.int64, lenstarts)
         util.call(context, builder, kernel,
@@ -294,18 +304,23 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
     elif isinstance(headtpe, numba.types.SliceType):
         proxyslicein = numba.cgutils.create_struct_proxy(headtpe)(context, builder, value=headval)
 
-        if arraytpe.bitwidth == 64:
+        if arraytpe.indexname == "64":
             determine_carrylength = cpu.kernels.awkward_listarray64_getitem_next_range_carrylength
             fill_carry = cpu.kernels.awkward_listarray64_getitem_next_range_64
             determine_total = cpu.kernels.awkward_listarray64_getitem_next_range_counts_64
             fill_nextadvanced = cpu.kernels.awkward_listarray64_getitem_next_range_spreadadvanced_64
-        elif arraytpe.bitwidth == 32:
+        elif arraytpe.indexname == "32":
             determine_carrylength = cpu.kernels.awkward_listarray32_getitem_next_range_carrylength
             fill_carry = cpu.kernels.awkward_listarray32_getitem_next_range_64
             determine_total = cpu.kernels.awkward_listarray32_getitem_next_range_counts_64
             fill_nextadvanced = cpu.kernels.awkward_listarray32_getitem_next_range_spreadadvanced_64
+        elif arraytpe.indexname == "U32":
+            determine_carrylength = cpu.kernels.awkward_listarrayU32_getitem_next_range_carrylength
+            fill_carry = cpu.kernels.awkward_listarrayU32_getitem_next_range_64
+            determine_total = cpu.kernels.awkward_listarrayU32_getitem_next_range_counts_64
+            fill_nextadvanced = cpu.kernels.awkward_listarrayU32_getitem_next_range_spreadadvanced_64
         else:
-            raise AssertionError("unrecognized bitwidth")
+            raise AssertionError("unrecognized index type: {}".format(arraytpe.indexname))
 
         carrylength = numba.cgutils.alloca_once(builder, context.get_value_type(numba.int64))
         util.call(context, builder, determine_carrylength,
@@ -320,10 +335,10 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
              util.cast(context, builder, numba.intp, numba.int64, proxyslicein.step)),
             "in {}, indexing error".format(arraytpe.shortname))
 
-        nextoffsets = util.newindex(arraytpe.bitwidth, context, builder, numba.int64, builder.add(lenstarts, context.get_constant(numba.int64, 1)))
+        nextoffsets = util.newindex(arraytpe.indexname, context, builder, numba.int64, builder.add(lenstarts, context.get_constant(numba.int64, 1)))
         nextcarry = util.newindex64(context, builder, numba.int64, builder.load(carrylength))
         util.call(context, builder, fill_carry,
-            (util.arrayptr(context, builder, util.indextpe(arraytpe.bitwidth), nextoffsets),
+            (util.arrayptr(context, builder, util.indextpe(arraytpe.indexname), nextoffsets),
              util.arrayptr(context, builder, util.index64tpe, nextcarry),
              util.arrayptr(context, builder, arraytpe.offsetstpe, starts),
              util.arrayptr(context, builder, arraytpe.offsetstpe, stops),
@@ -346,7 +361,7 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
             total = numba.cgutils.alloca_once(builder, context.get_value_type(numba.int64))
             util.call(context, builder, determine_total,
                 (total,
-                 util.arrayptr(context, builder, util.indextpe(arraytpe.bitwidth), nextoffsets),
+                 util.arrayptr(context, builder, util.indextpe(arraytpe.indexname), nextoffsets),
                  lenstarts),
                 "in {}, indexing error".format(arraytpe.shortname))
 
@@ -354,14 +369,14 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
             util.call(context, builder, fill_nextadvanced,
                 (util.arrayptr(context, builder, util.index64tpe, nextadvanced),
                  util.arrayptr(context, builder, util.index64tpe, advanced),
-                 util.arrayptr(context, builder, util.indextpe(arraytpe.bitwidth), nextoffsets),
+                 util.arrayptr(context, builder, util.indextpe(arraytpe.indexname), nextoffsets),
                  lenstarts),
                 "in {}, indexing error".format(arraytpe.shortname))
 
             outcontenttpe = nextcontenttpe.getitem_next(tailtpe, True)
             outcontentval = nextcontenttpe.lower_getitem_next(context, builder, nextcontenttpe, tailtpe, nextcontentval, tailval, nextadvanced)
 
-        outtpe = awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(arraytpe.bitwidth), outcontenttpe, arraytpe.idtpe)
+        outtpe = awkward1._numba.array.listoffsetarray.ListOffsetArrayType(util.indextpe(arraytpe.indexname), outcontenttpe, arraytpe.idtpe)
         proxyout = numba.cgutils.create_struct_proxy(outtpe)(context, builder)
         proxyout.offsets = nextoffsets
         proxyout.content = outcontentval
@@ -383,20 +398,22 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
         lenflathead = util.arraylen(context, builder, util.int64tpe, flathead, totpe=numba.int64)
 
         if advanced is None:
-            if arraytpe.bitwidth == 64:
+            if arraytpe.indexname == "64":
                 kernel = cpu.kernels.awkward_listarray64_getitem_next_array_64
-            elif arraytpe.bitwidth == 32:
+            elif arraytpe.indexname == "32":
                 kernel = cpu.kernels.awkward_listarray32_getitem_next_array_64
+            elif arraytpe.indexname == "U32":
+                kernel = cpu.kernels.awkward_listarrayU32_getitem_next_array_64
             else:
-                raise AssertionError("unrecognized bitwidth")
+                raise AssertionError("unrecognized index type: {}".format(arraytpe.indexname))
 
             lencarry = builder.mul(lenstarts, lenflathead)
 
             nextcarry = util.newindex64(context, builder, numba.int64, lencarry)
             nextadvanced = util.newindex64(context, builder, numba.int64, lencarry)
-            nextoffsets = util.newindex(arraytpe.bitwidth, context, builder, numba.int64, lenoffsets)
+            nextoffsets = util.newindex(arraytpe.indexname, context, builder, numba.int64, lenoffsets)
             util.call(context, builder, kernel,
-                (util.arrayptr(context, builder, util.indextpe(arraytpe.bitwidth), nextoffsets),
+                (util.arrayptr(context, builder, util.indextpe(arraytpe.indexname), nextoffsets),
                  util.arrayptr(context, builder, util.index64tpe, nextcarry),
                  util.arrayptr(context, builder, util.index64tpe, nextadvanced),
                  util.arrayptr(context, builder, arraytpe.offsetstpe, starts),
@@ -415,7 +432,7 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
             contenttpe = nexttpe.getitem_next(tailtpe, True)
             contentval = nexttpe.lower_getitem_next(context, builder, nexttpe, tailtpe, nextval, tailval, nextadvanced)
 
-            outtpe = ListOffsetArrayType(util.indextpe(arraytpe.bitwidth), contenttpe, arraytpe.idtpe)
+            outtpe = ListOffsetArrayType(util.indextpe(arraytpe.indexname), contenttpe, arraytpe.idtpe)
             proxyout = numba.cgutils.create_struct_proxy(outtpe)(context, builder)
             proxyout.offsets = nextoffsets
             proxyout.content = contentval
@@ -424,12 +441,14 @@ def lower_getitem_next(context, builder, arraytpe, wheretpe, arrayval, whereval,
             return proxyout._getvalue()
 
         else:
-            if arraytpe.bitwidth == 64:
+            if arraytpe.indexname == "64":
                 kernel = cpu.kernels.awkward_listarray64_getitem_next_array_advanced_64
-            elif arraytpe.bitwidth == 32:
+            elif arraytpe.indexname == "32":
                 kernel = cpu.kernels.awkward_listarray32_getitem_next_array_advanced_64
+            elif arraytpe.indexname == "U32":
+                kernel = cpu.kernels.awkward_listarrayU32_getitem_next_array_advanced_64
             else:
-                raise AssertionError("unrecognized bitwidth")
+                raise AssertionError("unrecognized index type: {}".format(arraytpe.indexname))
 
             nextcarry = util.newindex64(context, builder, numba.int64, lenstarts)
             nextadvanced = util.newindex64(context, builder, numba.int64, lenstarts)
diff --git a/awkward1/_numba/cpu.py b/awkward1/_numba/cpu.py
index 660001d5c3..64b903940c 100644
--- a/awkward1/_numba/cpu.py
+++ b/awkward1/_numba/cpu.py
@@ -46,10 +46,14 @@ def __init__(self, dmm, fe_type):
     "int32_t": ctypes.c_int32,
     "int32_t *": ctypes.POINTER(ctypes.c_int32),
     "const int32_t *": ctypes.POINTER(ctypes.c_int32),
+    "uint32_t": ctypes.c_uint32,
+    "uint32_t *": ctypes.POINTER(ctypes.c_uint32),
+    "const uint32_t *": ctypes.POINTER(ctypes.c_uint32),
     "int64_t": ctypes.c_int64,
     "int64_t *": ctypes.POINTER(ctypes.c_int64),
     "const int64_t *": ctypes.POINTER(ctypes.c_int64),
     "Error": Error,
+    "ERROR": Error,
     "void": None,
     }
 
@@ -63,7 +67,7 @@ def __init__(self, dmm, fe_type):
                 params = [(x.find("./declname").text, x.find("./type").text) for x in xfcn.findall("./param")]
                 getattr(kernels, name).name = name
                 getattr(kernels, name).argtypes = [h2ctypes[t] for n, t in params]
-                if rettype == "Error":
+                if rettype == "Error" or rettype == "ERROR":
                     getattr(kernels, name).restype = None
                     tmp = numba.typing.ctypes_utils.make_function_type(getattr(kernels, name))
                     getattr(kernels, name).numbatpe = numba.types.functions.ExternalFunctionPointer(Error.numbatpe(*tmp.sig.args), tmp.get_pointer, cconv=tmp.cconv)
diff --git a/awkward1/_numba/util.py b/awkward1/_numba/util.py
index c11852b1cc..12e73cc5ed 100644
--- a/awkward1/_numba/util.py
+++ b/awkward1/_numba/util.py
@@ -13,17 +13,23 @@
 RefType = numba.int64
 
 index8tpe = numba.types.Array(numba.int8, 1, "C")
+indexU8tpe = numba.types.Array(numba.uint8, 1, "C")
 index32tpe = numba.types.Array(numba.int32, 1, "C")
+indexU32tpe = numba.types.Array(numba.uint32, 1, "C")
 index64tpe = numba.types.Array(numba.int64, 1, "C")
-def indextpe(bitwidth):
-    if bitwidth == 8:
-        return index8tpe
-    elif bitwidth == 32:
-        return index32tpe
-    elif bitwidth == 64:
+def indextpe(indexname):
+    if indexname == "64":
         return index64tpe
+    elif indexname == "32":
+        return index32tpe
+    elif indexname == "U32":
+        return indexU32tpe
+    elif indexname == "8":
+        return index8tpe
+    elif indexname == "U8":
+        return indexU8tpe
     else:
-        raise AssertionError(bitwidth)
+        raise AssertionError("unrecognized index type: {}".format(indexname))
 
 if not py27:
     exec("""
@@ -92,19 +98,27 @@ def call(context, builder, fcn, args, errormessage=None):
 
 def newindex8(context, builder, lentpe, lenval):
     return numba.targets.arrayobj.numpy_empty_nd(context, builder, index8tpe(lentpe), (lenval,))
+def newindexU8(context, builder, lentpe, lenval):
+    return numba.targets.arrayobj.numpy_empty_nd(context, builder, indexU8tpe(lentpe), (lenval,))
 def newindex32(context, builder, lentpe, lenval):
     return numba.targets.arrayobj.numpy_empty_nd(context, builder, index32tpe(lentpe), (lenval,))
+def newindexU32(context, builder, lentpe, lenval):
+    return numba.targets.arrayobj.numpy_empty_nd(context, builder, indexU32tpe(lentpe), (lenval,))
 def newindex64(context, builder, lentpe, lenval):
     return numba.targets.arrayobj.numpy_empty_nd(context, builder, index64tpe(lentpe), (lenval,))
-def newindex(bitwidth, context, builder, lentpe, lenval):
-    if bitwidth == 8:
-        return newindex8(context, builder, lentpe, lenval)
-    elif bitwidth == 32:
-        return newindex32(context, builder, lentpe, lenval)
-    elif bitwidth == 64:
+def newindex(indexname, context, builder, lentpe, lenval):
+    if indexname == "64":
         return newindex64(context, builder, lentpe, lenval)
+    elif indexname == "32":
+        return newindex32(context, builder, lentpe, lenval)
+    elif indexname == "U32":
+        return newindexU32(context, builder, lentpe, lenval)
+    elif indexname == "8":
+        return newindex8(context, builder, lentpe, lenval)
+    elif indexname == "U8":
+        return newindexU8(context, builder, lentpe, lenval)
     else:
-        raise AssertionError(bitwidth)
+        raise AssertionError("unrecognized index type: {}".format(indexname))
 
 @numba.jit(nopython=True)
 def shapeat(shapeat, array, at, ndim):
diff --git a/awkward1/signatures/ListOffsetArray_8cpp.xml b/awkward1/signatures/ListOffsetArray_8cpp.xml
index 865e812ee9..ddf87c5c4b 100644
--- a/awkward1/signatures/ListOffsetArray_8cpp.xml
+++ b/awkward1/signatures/ListOffsetArray_8cpp.xml
@@ -72,7 +72,7 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/libawkward/array/ListOffsetArray.cpp" line="28" column="11" bodyfile="src/libawkward/array/ListOffsetArray.cpp" bodystart="28" bodyend="30"/>
+        <location file="src/libawkward/array/ListOffsetArray.cpp" line="31" column="11" bodyfile="src/libawkward/array/ListOffsetArray.cpp" bodystart="31" bodyend="33"/>
       </memberdef>
       <memberdef kind="function" id="namespaceawkward_1aa3d73a21953e0578aa577329c38dc0ed" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
@@ -94,7 +94,7 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/libawkward/array/ListOffsetArray.cpp" line="33" column="11" bodyfile="src/libawkward/array/ListOffsetArray.cpp" bodystart="33" bodyend="35"/>
+        <location file="src/libawkward/array/ListOffsetArray.cpp" line="36" column="11" bodyfile="src/libawkward/array/ListOffsetArray.cpp" bodystart="36" bodyend="38"/>
       </memberdef>
       </sectiondef>
     <briefdescription>
diff --git a/awkward1/signatures/NumpyArray_8cpp.xml b/awkward1/signatures/NumpyArray_8cpp.xml
index b291b6cf56..308a9755f2 100644
--- a/awkward1/signatures/NumpyArray_8cpp.xml
+++ b/awkward1/signatures/NumpyArray_8cpp.xml
@@ -74,7 +74,92 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/libawkward/array/NumpyArray.cpp" line="73" column="8" bodyfile="src/libawkward/array/NumpyArray.cpp" bodystart="73" bodyend="97"/>
+        <location file="src/libawkward/array/NumpyArray.cpp" line="77" column="8" bodyfile="src/libawkward/array/NumpyArray.cpp" bodystart="77" bodyend="101"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1aee7ebf77ca27982c93a28eb452a2728f" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>void</type>
+        <definition>void awkward::tojson_boolean</definition>
+        <argsstring>(ToJson &amp;builder, bool *array, int64_t length)</argsstring>
+        <name>tojson_boolean</name>
+        <param>
+          <type>ToJson &amp;</type>
+          <declname>builder</declname>
+        </param>
+        <param>
+          <type>bool *</type>
+          <declname>array</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>length</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/array/NumpyArray.cpp" line="184" column="8" bodyfile="src/libawkward/array/NumpyArray.cpp" bodystart="184" bodyend="188"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1a30008d57ae076e81a759b7314fea35bc" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+          <param>
+            <type>typename T</type>
+          </param>
+        </templateparamlist>
+        <type>void</type>
+        <definition>void awkward::tojson_integer</definition>
+        <argsstring>(ToJson &amp;builder, T *array, int64_t length)</argsstring>
+        <name>tojson_integer</name>
+        <param>
+          <type>ToJson &amp;</type>
+          <declname>builder</declname>
+        </param>
+        <param>
+          <type>T *</type>
+          <declname>array</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>length</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/array/NumpyArray.cpp" line="191" column="8" bodyfile="src/libawkward/array/NumpyArray.cpp" bodystart="191" bodyend="195"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1a481afc11c18742f08ad0935f0252c41d" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+          <param>
+            <type>typename T</type>
+          </param>
+        </templateparamlist>
+        <type>void</type>
+        <definition>void awkward::tojson_real</definition>
+        <argsstring>(ToJson &amp;builder, T *array, int64_t length)</argsstring>
+        <name>tojson_real</name>
+        <param>
+          <type>ToJson &amp;</type>
+          <declname>builder</declname>
+        </param>
+        <param>
+          <type>T *</type>
+          <declname>array</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>length</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/array/NumpyArray.cpp" line="198" column="8" bodyfile="src/libawkward/array/NumpyArray.cpp" bodystart="198" bodyend="202"/>
       </memberdef>
       <memberdef kind="function" id="namespaceawkward_1adf8a5960d7cc8e8447e7357e7416a1dd" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <type>const std::vector&lt; ssize_t &gt;</type>
@@ -91,7 +176,7 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/libawkward/array/NumpyArray.cpp" line="324" column="21" bodyfile="src/libawkward/array/NumpyArray.cpp" bodystart="324" bodyend="333"/>
+        <location file="src/libawkward/array/NumpyArray.cpp" line="409" column="21" bodyfile="src/libawkward/array/NumpyArray.cpp" bodystart="409" bodyend="418"/>
       </memberdef>
       <memberdef kind="function" id="namespaceawkward_1aadc1072e0733b797c5e796c493958e92" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <type>const std::vector&lt; ssize_t &gt;</type>
@@ -108,7 +193,7 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/libawkward/array/NumpyArray.cpp" line="335" column="21" bodyfile="src/libawkward/array/NumpyArray.cpp" bodystart="335" bodyend="342"/>
+        <location file="src/libawkward/array/NumpyArray.cpp" line="420" column="21" bodyfile="src/libawkward/array/NumpyArray.cpp" bodystart="420" bodyend="427"/>
       </memberdef>
       </sectiondef>
     <briefdescription>
diff --git a/awkward1/signatures/cpu-kernels_2util_8cpp.xml b/awkward1/signatures/cpu-kernels_2util_8cpp.xml
index 6ed44e0983..ee1767ce62 100644
--- a/awkward1/signatures/cpu-kernels_2util_8cpp.xml
+++ b/awkward1/signatures/cpu-kernels_2util_8cpp.xml
@@ -21,9 +21,9 @@
       </node>
     </incdepgraph>
       <sectiondef kind="func">
-      <memberdef kind="function" id="cpu-kernels_2util_8cpp_1a21deb91e044295ebec4e533139c804ba" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error success</definition>
+      <memberdef kind="function" id="cpu-kernels_2util_8cpp_1aa97e28bbb2153e79581b030cd1b7c9ad" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>struct Error</type>
+        <definition>struct Error success</definition>
         <argsstring>()</argsstring>
         <name>success</name>
         <briefdescription>
@@ -32,11 +32,11 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/util.cpp" line="7" column="7" bodyfile="src/cpu-kernels/util.cpp" bodystart="7" bodyend="14"/>
+        <location file="src/cpu-kernels/util.cpp" line="55" column="7" bodyfile="src/cpu-kernels/util.cpp" bodystart="7" bodyend="14"/>
       </memberdef>
-      <memberdef kind="function" id="cpu-kernels_2util_8cpp_1a525c8383a6f1519e9c905538a0def33f" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error failure</definition>
+      <memberdef kind="function" id="cpu-kernels_2util_8cpp_1a06d96ca5e0b2c7c68b2cc2ee9971d208" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>struct Error</type>
+        <definition>struct Error failure</definition>
         <argsstring>(const char *str, int64_t location, int64_t attempt)</argsstring>
         <name>failure</name>
         <param>
@@ -57,7 +57,7 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/util.cpp" line="16" column="7" bodyfile="src/cpu-kernels/util.cpp" bodystart="16" bodyend="23"/>
+        <location file="src/cpu-kernels/util.cpp" line="55" column="7" bodyfile="src/cpu-kernels/util.cpp" bodystart="16" bodyend="23"/>
       </memberdef>
       </sectiondef>
     <briefdescription>
diff --git a/awkward1/signatures/getitem_8cpp.xml b/awkward1/signatures/getitem_8cpp.xml
index 34ea78f08e..1932861a39 100644
--- a/awkward1/signatures/getitem_8cpp.xml
+++ b/awkward1/signatures/getitem_8cpp.xml
@@ -58,14 +58,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="7" column="6" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="7" bodyend="33"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1ae300c47cc2d5fbfeecf3984e3cab2622" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a0eaf184155be82327e43972bf6e0214f" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_regularize_arrayslice</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_regularize_arrayslice</definition>
         <argsstring>(T *flatheadptr, int64_t lenflathead, int64_t length)</argsstring>
         <name>awkward_regularize_arrayslice</name>
         <param>
@@ -88,9 +88,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="36" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="36" bodyend="47"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a9f2ca6a7d769d9983d38096abde78904" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_regularize_arrayslice_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1acbf42368b35f550c2d1bde6aa21ffad3" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_regularize_arrayslice_64</definition>
         <argsstring>(int64_t *flatheadptr, int64_t lenflathead, int64_t length)</argsstring>
         <name>awkward_regularize_arrayslice_64</name>
         <param>
@@ -113,14 +113,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="48" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="48" bodyend="50"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a0b32f8d4c12ad3479caf26f000d2f4a5" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1ad250f2a56c89c53d7e93d1f5e8c09342" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_slicearray_ravel</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_slicearray_ravel</definition>
         <argsstring>(T *toptr, const T *fromptr, int64_t ndim, const int64_t *shape, const int64_t *strides)</argsstring>
         <name>awkward_slicearray_ravel</name>
         <param>
@@ -151,9 +151,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="53" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="53" bodyend="68"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a16cce0ea90cdd11d1fddbd88dd9af3ad" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_slicearray_ravel_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a4d5004b5cab502313eb620842bf45b1a" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_slicearray_ravel_64</definition>
         <argsstring>(int64_t *toptr, const int64_t *fromptr, int64_t ndim, const int64_t *shape, const int64_t *strides)</argsstring>
         <name>awkward_slicearray_ravel_64</name>
         <param>
@@ -184,14 +184,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="69" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="69" bodyend="71"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a9046531284af0c4074534d38312aae1e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a37455b98cc325ef3edba6f61e9bba729" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_carry_arange</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_carry_arange</definition>
         <argsstring>(T *toptr, int64_t length)</argsstring>
         <name>awkward_carry_arange</name>
         <param>
@@ -210,9 +210,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="74" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="74" bodyend="79"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1abc33aefb35c2e2ef20c0ec30cbb5c8b4" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_carry_arange_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1abcef3019b05fc4287c878a5f6c0a962b" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_carry_arange_64</definition>
         <argsstring>(int64_t *toptr, int64_t length)</argsstring>
         <name>awkward_carry_arange_64</name>
         <param>
@@ -231,7 +231,7 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="80" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="80" bodyend="82"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a1a875fc5440b943acea6f54d6a45c3f5" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1ae88233cc7236563ffedab4b90ff62795" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename ID</type>
@@ -240,8 +240,8 @@
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_identity_getitem_carry</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_identity_getitem_carry</definition>
         <argsstring>(ID *newidentityptr, const ID *identityptr, const T *carryptr, int64_t lencarry, int64_t offset, int64_t width, int64_t length)</argsstring>
         <name>awkward_identity_getitem_carry</name>
         <param>
@@ -280,9 +280,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="85" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="85" bodyend="95"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a08dc7949f84425100a92f83bda2ac165" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_identity32_getitem_carry_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a676b71b871c32dc413baa2deb02653df" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_identity32_getitem_carry_64</definition>
         <argsstring>(int32_t *newidentityptr, const int32_t *identityptr, const int64_t *carryptr, int64_t lencarry, int64_t offset, int64_t width, int64_t length)</argsstring>
         <name>awkward_identity32_getitem_carry_64</name>
         <param>
@@ -321,9 +321,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="96" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="96" bodyend="98"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a512f077c8daf5524c84b3804c0cdf6f6" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_identity64_getitem_carry_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1ad331bbb4b5c8dc946c81f6747d4ebd1f" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_identity64_getitem_carry_64</definition>
         <argsstring>(int64_t *newidentityptr, const int64_t *identityptr, const int64_t *carryptr, int64_t lencarry, int64_t offset, int64_t width, int64_t length)</argsstring>
         <name>awkward_identity64_getitem_carry_64</name>
         <param>
@@ -362,14 +362,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="99" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="99" bodyend="101"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1ac846ea4e178e519a01668ac062681d70" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a642138c5d013a0f6fb009854430b0f6b" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_contiguous_init</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_contiguous_init</definition>
         <argsstring>(T *toptr, int64_t skip, int64_t stride)</argsstring>
         <name>awkward_numpyarray_contiguous_init</name>
         <param>
@@ -392,9 +392,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="104" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="104" bodyend="109"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a7ab8e175f61b26f5c4178a00c4825a24" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_contiguous_init_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a2d0d27d8ad577b88b1e2b66521462784" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_contiguous_init_64</definition>
         <argsstring>(int64_t *toptr, int64_t skip, int64_t stride)</argsstring>
         <name>awkward_numpyarray_contiguous_init_64</name>
         <param>
@@ -417,14 +417,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="110" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="110" bodyend="112"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1aa436e065b3b65e1f56855e30cc9e375e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1af728770ad3a2d91e1906ffbb1cf72574" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_contiguous_copy</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_contiguous_copy</definition>
         <argsstring>(uint8_t *toptr, const uint8_t *fromptr, int64_t len, int64_t stride, int64_t offset, const T *pos)</argsstring>
         <name>awkward_numpyarray_contiguous_copy</name>
         <param>
@@ -459,9 +459,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="115" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="115" bodyend="120"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a929ca539b1e62b870dda37da35a2c7f0" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_contiguous_copy_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a5268b5b040f031b87090ec0e6f95b569" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_contiguous_copy_64</definition>
         <argsstring>(uint8_t *toptr, const uint8_t *fromptr, int64_t len, int64_t stride, int64_t offset, const int64_t *pos)</argsstring>
         <name>awkward_numpyarray_contiguous_copy_64</name>
         <param>
@@ -496,14 +496,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="121" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="121" bodyend="123"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a012d8bca45020ead8b3713ea47dd7dd7" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1ad789067fce5a5d158d676c1d3f1b5d57" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_contiguous_next</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_contiguous_next</definition>
         <argsstring>(T *topos, const T *frompos, int64_t len, int64_t skip, int64_t stride)</argsstring>
         <name>awkward_numpyarray_contiguous_next</name>
         <param>
@@ -534,9 +534,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="126" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="126" bodyend="133"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1af676650b780ff05799fe387a855379b9" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_contiguous_next_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a34f09a986da622b715b9d9c73bc9a44a" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_contiguous_next_64</definition>
         <argsstring>(int64_t *topos, const int64_t *frompos, int64_t len, int64_t skip, int64_t stride)</argsstring>
         <name>awkward_numpyarray_contiguous_next_64</name>
         <param>
@@ -567,14 +567,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="134" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="134" bodyend="136"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a9a06d5708b75dedb4efdf2de1975dca8" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a1294a006f79517a63ea05ca910c3960d" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_null</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_null</definition>
         <argsstring>(uint8_t *toptr, const uint8_t *fromptr, int64_t len, int64_t stride, int64_t offset, const T *pos)</argsstring>
         <name>awkward_numpyarray_getitem_next_null</name>
         <param>
@@ -609,9 +609,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="139" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="139" bodyend="144"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a3da09ff1b744ab5442fedc9998266817" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_null_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1afa769b0e6e4bf0b977e31cd5ac5c7e23" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_null_64</definition>
         <argsstring>(uint8_t *toptr, const uint8_t *fromptr, int64_t len, int64_t stride, int64_t offset, const int64_t *pos)</argsstring>
         <name>awkward_numpyarray_getitem_next_null_64</name>
         <param>
@@ -646,14 +646,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="145" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="145" bodyend="147"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1aa9f782df302c351a8307ab974c8e1023" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a9e955139ce806614d6df2aad9fd36ad0" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_at</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_at</definition>
         <argsstring>(T *nextcarryptr, const T *carryptr, int64_t lencarry, int64_t skip, int64_t at)</argsstring>
         <name>awkward_numpyarray_getitem_next_at</name>
         <param>
@@ -684,9 +684,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="150" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="150" bodyend="155"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a5f412d4560ffc73bcadb80839b5e997e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_at_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a242e36a3757747e734c41a93d04e0fdb" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_at_64</definition>
         <argsstring>(int64_t *nextcarryptr, const int64_t *carryptr, int64_t lencarry, int64_t skip, int64_t at)</argsstring>
         <name>awkward_numpyarray_getitem_next_at_64</name>
         <param>
@@ -717,14 +717,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="156" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="156" bodyend="158"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a178c16e61d6e48593f60e9c8c145fee3" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a4f468fb19a867b3dce75edba73086a59" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_range</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_range</definition>
         <argsstring>(T *nextcarryptr, const T *carryptr, int64_t lencarry, int64_t lenhead, int64_t skip, int64_t start, int64_t step)</argsstring>
         <name>awkward_numpyarray_getitem_next_range</name>
         <param>
@@ -763,9 +763,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="161" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="161" bodyend="168"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a3adca3c781ec31b45a3c8a9a4f3c8e95" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_range_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1adfb97b3adef2becb51d4031bba5b1a7d" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_range_64</definition>
         <argsstring>(int64_t *nextcarryptr, const int64_t *carryptr, int64_t lencarry, int64_t lenhead, int64_t skip, int64_t start, int64_t step)</argsstring>
         <name>awkward_numpyarray_getitem_next_range_64</name>
         <param>
@@ -804,14 +804,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="169" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="169" bodyend="171"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a2f3e5eb423881b2aa646dd3847d4dee2" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1ae9cc2f93dc9a18c0381acea0c0793d48" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_range_advanced</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_range_advanced</definition>
         <argsstring>(T *nextcarryptr, T *nextadvancedptr, const T *carryptr, const T *advancedptr, int64_t lencarry, int64_t lenhead, int64_t skip, int64_t start, int64_t step)</argsstring>
         <name>awkward_numpyarray_getitem_next_range_advanced</name>
         <param>
@@ -858,9 +858,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="174" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="174" bodyend="182"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a54f803acd949b972446ae55ca48fb81a" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_range_advanced_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a3a46808a2f3c60c36251eca9a849b480" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_range_advanced_64</definition>
         <argsstring>(int64_t *nextcarryptr, int64_t *nextadvancedptr, const int64_t *carryptr, const int64_t *advancedptr, int64_t lencarry, int64_t lenhead, int64_t skip, int64_t start, int64_t step)</argsstring>
         <name>awkward_numpyarray_getitem_next_range_advanced_64</name>
         <param>
@@ -907,14 +907,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="183" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="183" bodyend="185"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1ad635d33b2dd302eba2c73f6a2b96132f" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a93c0900d662a97013db1957941fd75c8" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_array</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_array</definition>
         <argsstring>(T *nextcarryptr, T *nextadvancedptr, const T *carryptr, const T *flatheadptr, int64_t lencarry, int64_t lenflathead, int64_t skip)</argsstring>
         <name>awkward_numpyarray_getitem_next_array</name>
         <param>
@@ -953,9 +953,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="188" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="188" bodyend="196"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1af91de98ee4da3fc29d910b532a268a19" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_array_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1afcfb84dd3cdabbf18e6dbef0ce4a95a8" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_array_64</definition>
         <argsstring>(int64_t *nextcarryptr, int64_t *nextadvancedptr, const int64_t *carryptr, const int64_t *flatheadptr, int64_t lencarry, int64_t lenflathead, int64_t skip)</argsstring>
         <name>awkward_numpyarray_getitem_next_array_64</name>
         <param>
@@ -994,14 +994,14 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="197" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="197" bodyend="199"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1aff8d9de200cfd0e8c9c412ab7e3801ec" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a0f368feb3f0a3030b058548675c2d894" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_array_advanced</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_array_advanced</definition>
         <argsstring>(T *nextcarryptr, const T *carryptr, const T *advancedptr, const T *flatheadptr, int64_t lencarry, int64_t skip)</argsstring>
         <name>awkward_numpyarray_getitem_next_array_advanced</name>
         <param>
@@ -1036,9 +1036,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="202" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="202" bodyend="207"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a2e2cff26f34d5112a8e2a32450d573f3" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_numpyarray_getitem_next_array_advanced_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1ad6beec6bff4685f1a4a8adec4c7143fb" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_numpyarray_getitem_next_array_advanced_64</definition>
         <argsstring>(int64_t *nextcarryptr, const int64_t *carryptr, const int64_t *advancedptr, const int64_t *flatheadptr, int64_t lencarry, int64_t skip)</argsstring>
         <name>awkward_numpyarray_getitem_next_array_advanced_64</name>
         <param>
@@ -1073,7 +1073,7 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="208" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="208" bodyend="210"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a41b0955f91277fa11060d64364100d33" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a6df44dcc4623a9129e6454626e4a3093" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename C</type>
@@ -1082,8 +1082,8 @@
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_listarray_getitem_next_at</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray_getitem_next_at</definition>
         <argsstring>(T *tocarry, const C *fromstarts, const C *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at)</argsstring>
         <name>awkward_listarray_getitem_next_at</name>
         <param>
@@ -1122,9 +1122,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="213" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="213" bodyend="226"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a489518e2b93f98620d5bd658630c0c80" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray32_getitem_next_at_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1aea79fcd8ecc7a62859ff78907170c189" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray32_getitem_next_at_64</definition>
         <argsstring>(int64_t *tocarry, const int32_t *fromstarts, const int32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at)</argsstring>
         <name>awkward_listarray32_getitem_next_at_64</name>
         <param>
@@ -1163,9 +1163,50 @@
         </inbodydescription>
         <location file="src/cpu-kernels/getitem.cpp" line="227" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="227" bodyend="229"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1abef2dff7eac65f5bef85d72727cc6c65" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray64_getitem_next_at_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a09f068f678e25354ab9920dc13255238" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarrayU32_getitem_next_at_64</definition>
+        <argsstring>(int64_t *tocarry, const uint32_t *fromstarts, const uint32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at)</argsstring>
+        <name>awkward_listarrayU32_getitem_next_at_64</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>at</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/cpu-kernels/getitem.cpp" line="230" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="230" bodyend="232"/>
+      </memberdef>
+      <memberdef kind="function" id="getitem_8cpp_1a15b473cecafa2845b3ea40b0b667b6a5" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray64_getitem_next_at_64</definition>
         <argsstring>(int64_t *tocarry, const int64_t *fromstarts, const int64_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at)</argsstring>
         <name>awkward_listarray64_getitem_next_at_64</name>
         <param>
@@ -1202,16 +1243,16 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="230" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="230" bodyend="232"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="233" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="233" bodyend="235"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a67fcc2466389188bec7a742c565eca67" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1acfea604578a617ace1a74a5c2eb598b3" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename C</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_listarray_getitem_next_range_carrylength</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray_getitem_next_range_carrylength</definition>
         <argsstring>(int64_t *carrylength, const C *fromstarts, const C *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
         <name>awkward_listarray_getitem_next_range_carrylength</name>
         <param>
@@ -1256,11 +1297,11 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="235" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="235" bodyend="254"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="238" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="238" bodyend="257"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1aa0abc977f8e0c544d255a49783e1d664" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray32_getitem_next_range_carrylength</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a107e12aa8636e70375cc42d46ec86b23" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray32_getitem_next_range_carrylength</definition>
         <argsstring>(int64_t *carrylength, const int32_t *fromstarts, const int32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
         <name>awkward_listarray32_getitem_next_range_carrylength</name>
         <param>
@@ -1305,11 +1346,60 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="255" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="255" bodyend="257"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="258" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="258" bodyend="260"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1abaf47bc1a4f120752ad286eec1f1dbee" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray64_getitem_next_range_carrylength</definition>
+      <memberdef kind="function" id="getitem_8cpp_1ac7be2c7d4257e0e38dc96e82316fe6fc" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarrayU32_getitem_next_range_carrylength</definition>
+        <argsstring>(int64_t *carrylength, const uint32_t *fromstarts, const uint32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
+        <name>awkward_listarrayU32_getitem_next_range_carrylength</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>carrylength</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>start</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stop</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>step</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/cpu-kernels/getitem.cpp" line="261" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="261" bodyend="263"/>
+      </memberdef>
+      <memberdef kind="function" id="getitem_8cpp_1a62d1e39f7e7934c88080f60bd11f8e34" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray64_getitem_next_range_carrylength</definition>
         <argsstring>(int64_t *carrylength, const int64_t *fromstarts, const int64_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
         <name>awkward_listarray64_getitem_next_range_carrylength</name>
         <param>
@@ -1354,9 +1444,9 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="258" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="258" bodyend="260"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="264" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="264" bodyend="266"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1ac80be75daf4723aeee8aafeb459c3d46" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a5e1d3332333a32865d2f5c9fd3548328" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename C</type>
@@ -1365,8 +1455,8 @@
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_listarray_getitem_next_range</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray_getitem_next_range</definition>
         <argsstring>(C *tooffsets, T *tocarry, const C *fromstarts, const C *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
         <name>awkward_listarray_getitem_next_range</name>
         <param>
@@ -1415,11 +1505,11 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="263" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="263" bodyend="286"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="269" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="269" bodyend="292"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a3ef2ac0d6a2162a9ee9a8349dd7438b6" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray32_getitem_next_range_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a5620b1acf314ed2222bdb33a75f25b3d" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray32_getitem_next_range_64</definition>
         <argsstring>(int32_t *tooffsets, int64_t *tocarry, const int32_t *fromstarts, const int32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
         <name>awkward_listarray32_getitem_next_range_64</name>
         <param>
@@ -1468,11 +1558,64 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="287" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="287" bodyend="289"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="293" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="293" bodyend="295"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a3431237f8ec2998fc70329a0bfc5628c" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray64_getitem_next_range_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a317e8ea50a0ef306c058897206f84ce0" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarrayU32_getitem_next_range_64</definition>
+        <argsstring>(uint32_t *tooffsets, int64_t *tocarry, const uint32_t *fromstarts, const uint32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
+        <name>awkward_listarrayU32_getitem_next_range_64</name>
+        <param>
+          <type>uint32_t *</type>
+          <declname>tooffsets</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>start</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stop</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>step</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/cpu-kernels/getitem.cpp" line="296" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="296" bodyend="298"/>
+      </memberdef>
+      <memberdef kind="function" id="getitem_8cpp_1acc85ad77e728f5f41434170be48e35aa" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray64_getitem_next_range_64</definition>
         <argsstring>(int64_t *tooffsets, int64_t *tocarry, const int64_t *fromstarts, const int64_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
         <name>awkward_listarray64_getitem_next_range_64</name>
         <param>
@@ -1521,9 +1664,9 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="290" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="290" bodyend="292"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="299" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="299" bodyend="301"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1ac4011afba6025e590b6770224cb478cb" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a0b825f888faa9660a4209dd85580f1c6" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename C</type>
@@ -1532,8 +1675,8 @@
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_listarray_getitem_next_range_counts</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray_getitem_next_range_counts</definition>
         <argsstring>(int64_t *total, const C *fromoffsets, int64_t lenstarts)</argsstring>
         <name>awkward_listarray_getitem_next_range_counts</name>
         <param>
@@ -1554,11 +1697,11 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="295" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="295" bodyend="301"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="304" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="304" bodyend="310"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a3cd565be6eff29458da9cf4574e4aec5" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray32_getitem_next_range_counts_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1ac0c53f6001ef53e64739ca6f883de30c" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray32_getitem_next_range_counts_64</definition>
         <argsstring>(int64_t *total, const int32_t *fromoffsets, int64_t lenstarts)</argsstring>
         <name>awkward_listarray32_getitem_next_range_counts_64</name>
         <param>
@@ -1579,11 +1722,36 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="302" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="302" bodyend="304"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="311" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="311" bodyend="313"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1af5bb9a4166dfa32d84fe73b8b827954e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray64_getitem_next_range_counts_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a63b6c8499b6c8c8aaeb006c13dcf565f" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarrayU32_getitem_next_range_counts_64</definition>
+        <argsstring>(int64_t *total, const uint32_t *fromoffsets, int64_t lenstarts)</argsstring>
+        <name>awkward_listarrayU32_getitem_next_range_counts_64</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>total</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromoffsets</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/cpu-kernels/getitem.cpp" line="314" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="314" bodyend="316"/>
+      </memberdef>
+      <memberdef kind="function" id="getitem_8cpp_1ac8b96d8cb065474d82046d205a97ef5c" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray64_getitem_next_range_counts_64</definition>
         <argsstring>(int64_t *total, const int64_t *fromoffsets, int64_t lenstarts)</argsstring>
         <name>awkward_listarray64_getitem_next_range_counts_64</name>
         <param>
@@ -1604,9 +1772,9 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="305" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="305" bodyend="307"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="317" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="317" bodyend="319"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1abe238e91b03782866d7e5ab10d0f64ad" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a9725a7526fa7f70dae6095d24810ad7a" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename C</type>
@@ -1615,8 +1783,8 @@
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_listarray_getitem_next_range_spreadadvanced</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray_getitem_next_range_spreadadvanced</definition>
         <argsstring>(T *toadvanced, const T *fromadvanced, const C *fromoffsets, int64_t lenstarts)</argsstring>
         <name>awkward_listarray_getitem_next_range_spreadadvanced</name>
         <param>
@@ -1641,11 +1809,11 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="310" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="310" bodyend="318"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="322" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="322" bodyend="330"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1adfe3a5abb34822d626ceac8c65f19832" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray32_getitem_next_range_spreadadvanced_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1aa32646c54492a4d05df12c4e217b39fd" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray32_getitem_next_range_spreadadvanced_64</definition>
         <argsstring>(int64_t *toadvanced, const int64_t *fromadvanced, const int32_t *fromoffsets, int64_t lenstarts)</argsstring>
         <name>awkward_listarray32_getitem_next_range_spreadadvanced_64</name>
         <param>
@@ -1670,11 +1838,40 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="319" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="319" bodyend="321"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="331" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="331" bodyend="333"/>
+      </memberdef>
+      <memberdef kind="function" id="getitem_8cpp_1a259429917ed2a685a68323ec82df58b2" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarrayU32_getitem_next_range_spreadadvanced_64</definition>
+        <argsstring>(int64_t *toadvanced, const int64_t *fromadvanced, const uint32_t *fromoffsets, int64_t lenstarts)</argsstring>
+        <name>awkward_listarrayU32_getitem_next_range_spreadadvanced_64</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromadvanced</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromoffsets</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/cpu-kernels/getitem.cpp" line="334" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="334" bodyend="336"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1abe492091dc60f74c3df5a1c5abe50792" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray64_getitem_next_range_spreadadvanced_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a32485c323b0e80a07471597cf2d4706c" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray64_getitem_next_range_spreadadvanced_64</definition>
         <argsstring>(int64_t *toadvanced, const int64_t *fromadvanced, const int64_t *fromoffsets, int64_t lenstarts)</argsstring>
         <name>awkward_listarray64_getitem_next_range_spreadadvanced_64</name>
         <param>
@@ -1699,9 +1896,9 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="322" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="322" bodyend="324"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="337" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="337" bodyend="339"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1acc120c3c4a674e0dfceaf459c4d62252" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1ac15abae3933028f2f4802a3356456413" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename C</type>
@@ -1710,8 +1907,8 @@
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_listarray_getitem_next_array</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray_getitem_next_array</definition>
         <argsstring>(C *tooffsets, T *tocarry, T *toadvanced, const C *fromstarts, const C *fromstops, const T *fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
         <name>awkward_listarray_getitem_next_array</name>
         <param>
@@ -1764,11 +1961,11 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="327" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="327" bodyend="351"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="342" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="342" bodyend="366"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a6ec7b77e680981f22bf083bb676ccc01" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray32_getitem_next_array_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a0a8fbcdffd0aa7cd7b540299b6d6a599" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray32_getitem_next_array_64</definition>
         <argsstring>(int32_t *tooffsets, int64_t *tocarry, int64_t *toadvanced, const int32_t *fromstarts, const int32_t *fromstops, const int64_t *fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
         <name>awkward_listarray32_getitem_next_array_64</name>
         <param>
@@ -1821,11 +2018,68 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="352" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="352" bodyend="354"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="367" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="367" bodyend="369"/>
+      </memberdef>
+      <memberdef kind="function" id="getitem_8cpp_1aafa4f40815955776859fd35f1e06c5c9" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarrayU32_getitem_next_array_64</definition>
+        <argsstring>(uint32_t *tooffsets, int64_t *tocarry, int64_t *toadvanced, const uint32_t *fromstarts, const uint32_t *fromstops, const int64_t *fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
+        <name>awkward_listarrayU32_getitem_next_array_64</name>
+        <param>
+          <type>uint32_t *</type>
+          <declname>tooffsets</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencontent</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/cpu-kernels/getitem.cpp" line="370" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="370" bodyend="372"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1af35abdabe9c39d6fdd6ef1e9890dbd89" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray64_getitem_next_array_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1aeccb0b5fc5d8eec34f70de0b27a894a7" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray64_getitem_next_array_64</definition>
         <argsstring>(int64_t *tooffsets, int64_t *tocarry, int64_t *toadvanced, const int64_t *fromstarts, const int64_t *fromstops, const int64_t *fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
         <name>awkward_listarray64_getitem_next_array_64</name>
         <param>
@@ -1878,9 +2132,9 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="355" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="355" bodyend="357"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="373" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="373" bodyend="375"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a05cedfd06e695d8370b8f9d3883867d7" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a240137941c709b11deac3ffb5e88e851" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename C</type>
@@ -1889,8 +2143,8 @@
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_listarray_getitem_next_array_advanced</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray_getitem_next_array_advanced</definition>
         <argsstring>(T *tocarry, T *toadvanced, const C *fromstarts, const C *fromstops, const T *fromarray, const T *fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
         <name>awkward_listarray_getitem_next_array_advanced</name>
         <param>
@@ -1943,11 +2197,11 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="360" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="360" bodyend="383"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="378" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="378" bodyend="401"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a4e94a81c0bdae571db5f767aef52f1fc" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray32_getitem_next_array_advanced_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a7a49b6a84413de2b3ff29eb8c6d03e3e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray32_getitem_next_array_advanced_64</definition>
         <argsstring>(int64_t *tocarry, int64_t *toadvanced, const int32_t *fromstarts, const int32_t *fromstops, const int64_t *fromarray, const int64_t *fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
         <name>awkward_listarray32_getitem_next_array_advanced_64</name>
         <param>
@@ -2000,11 +2254,68 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="384" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="384" bodyend="386"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="402" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="402" bodyend="404"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a9168561c0b444beb08b7bf296e5ac899" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray64_getitem_next_array_advanced_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a0331c02c4d4c3326c2effefbac16a1d1" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarrayU32_getitem_next_array_advanced_64</definition>
+        <argsstring>(int64_t *tocarry, int64_t *toadvanced, const uint32_t *fromstarts, const uint32_t *fromstops, const int64_t *fromarray, const int64_t *fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
+        <name>awkward_listarrayU32_getitem_next_array_advanced_64</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromarray</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromadvanced</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencontent</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/cpu-kernels/getitem.cpp" line="405" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="405" bodyend="407"/>
+      </memberdef>
+      <memberdef kind="function" id="getitem_8cpp_1a1ed681c204a7a1841fb9f969c817b0ff" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray64_getitem_next_array_advanced_64</definition>
         <argsstring>(int64_t *tocarry, int64_t *toadvanced, const int64_t *fromstarts, const int64_t *fromstops, const int64_t *fromarray, const int64_t *fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
         <name>awkward_listarray64_getitem_next_array_advanced_64</name>
         <param>
@@ -2057,9 +2368,9 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="387" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="387" bodyend="389"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="408" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="408" bodyend="410"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a4224ccf010d94c447efb8f9bacd6986a" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="getitem_8cpp_1a46a4fa541871744b859a90c17fd66b8b" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename C</type>
@@ -2068,8 +2379,8 @@
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_listarray_getitem_carry</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray_getitem_carry</definition>
         <argsstring>(C *tostarts, C *tostops, const C *fromstarts, const C *fromstops, const T *fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry)</argsstring>
         <name>awkward_listarray_getitem_carry</name>
         <param>
@@ -2114,11 +2425,11 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="392" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="392" bodyend="401"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="413" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="413" bodyend="422"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a8e6426aeb4b36351a5a2acbe0e8909e2" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray32_getitem_carry_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a1be4a059959dfb86ebf3b03bb8ff158f" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray32_getitem_carry_64</definition>
         <argsstring>(int32_t *tostarts, int32_t *tostops, const int32_t *fromstarts, const int32_t *fromstops, const int64_t *fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry)</argsstring>
         <name>awkward_listarray32_getitem_carry_64</name>
         <param>
@@ -2163,11 +2474,60 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="402" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="402" bodyend="404"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="423" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="423" bodyend="425"/>
       </memberdef>
-      <memberdef kind="function" id="getitem_8cpp_1a36e50f491823e64a55c0dae418d60abf" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_listarray64_getitem_carry_64</definition>
+      <memberdef kind="function" id="getitem_8cpp_1a477e4f491c7aa1130d6609505a23ec5f" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarrayU32_getitem_carry_64</definition>
+        <argsstring>(uint32_t *tostarts, uint32_t *tostops, const uint32_t *fromstarts, const uint32_t *fromstops, const int64_t *fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry)</argsstring>
+        <name>awkward_listarrayU32_getitem_carry_64</name>
+        <param>
+          <type>uint32_t *</type>
+          <declname>tostarts</declname>
+        </param>
+        <param>
+          <type>uint32_t *</type>
+          <declname>tostops</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromcarry</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencarry</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/cpu-kernels/getitem.cpp" line="426" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="426" bodyend="428"/>
+      </memberdef>
+      <memberdef kind="function" id="getitem_8cpp_1ac27f4fad0770a9335d5410d9dce31582" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_listarray64_getitem_carry_64</definition>
         <argsstring>(int64_t *tostarts, int64_t *tostops, const int64_t *fromstarts, const int64_t *fromstops, const int64_t *fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry)</argsstring>
         <name>awkward_listarray64_getitem_carry_64</name>
         <param>
@@ -2212,7 +2572,7 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/getitem.cpp" line="405" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="405" bodyend="407"/>
+        <location file="src/cpu-kernels/getitem.cpp" line="429" column="7" bodyfile="src/cpu-kernels/getitem.cpp" bodystart="429" bodyend="431"/>
       </memberdef>
       </sectiondef>
     <briefdescription>
diff --git a/awkward1/signatures/identity_8cpp.xml b/awkward1/signatures/identity_8cpp.xml
index a6cf3d5f96..9b068899b2 100644
--- a/awkward1/signatures/identity_8cpp.xml
+++ b/awkward1/signatures/identity_8cpp.xml
@@ -15,14 +15,14 @@
       </node>
     </incdepgraph>
       <sectiondef kind="func">
-      <memberdef kind="function" id="identity_8cpp_1a7dd39cb44c3126176d60647ee1b1ac07" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="identity_8cpp_1aa436913b7f9184b42539c93fbf9d1821" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_new_identity</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_new_identity</definition>
         <argsstring>(T *toptr, int64_t length)</argsstring>
         <name>awkward_new_identity</name>
         <param>
@@ -41,9 +41,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/identity.cpp" line="6" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="6" bodyend="11"/>
       </memberdef>
-      <memberdef kind="function" id="identity_8cpp_1a692cff41e21761fe205e172218679306" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_new_identity32</definition>
+      <memberdef kind="function" id="identity_8cpp_1a974150042f8694b3a24ff623c2d3832c" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_new_identity32</definition>
         <argsstring>(int32_t *toptr, int64_t length)</argsstring>
         <name>awkward_new_identity32</name>
         <param>
@@ -62,9 +62,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/identity.cpp" line="12" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="12" bodyend="14"/>
       </memberdef>
-      <memberdef kind="function" id="identity_8cpp_1ada6b7237845c67c233026820565bf73d" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_new_identity64</definition>
+      <memberdef kind="function" id="identity_8cpp_1aef93142b307b31ee691d6cccb8e22c77" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_new_identity64</definition>
         <argsstring>(int64_t *toptr, int64_t length)</argsstring>
         <name>awkward_new_identity64</name>
         <param>
@@ -83,9 +83,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/identity.cpp" line="15" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="15" bodyend="17"/>
       </memberdef>
-      <memberdef kind="function" id="identity_8cpp_1a8bf3c663a05ba8517386251696bd6e33" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_identity32_to_identity64</definition>
+      <memberdef kind="function" id="identity_8cpp_1a57aff60803a08066d4d7b257fcc36726" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_identity32_to_identity64</definition>
         <argsstring>(int64_t *toptr, const int32_t *fromptr, int64_t length)</argsstring>
         <name>awkward_identity32_to_identity64</name>
         <param>
@@ -108,7 +108,7 @@
         </inbodydescription>
         <location file="src/cpu-kernels/identity.cpp" line="19" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="19" bodyend="24"/>
       </memberdef>
-      <memberdef kind="function" id="identity_8cpp_1a7940e8286413a007a413f733f95c3c29" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="identity_8cpp_1ae93ca85c3f8915f576a26e7d2853a57e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <templateparamlist>
           <param>
             <type>typename ID</type>
@@ -117,8 +117,8 @@
             <type>typename T</type>
           </param>
         </templateparamlist>
-        <type>Error</type>
-        <definition>Error awkward_identity_from_listarray</definition>
+        <type>ERROR</type>
+        <definition>ERROR awkward_identity_from_listarray</definition>
         <argsstring>(ID *toptr, const ID *fromptr, const T *fromstarts, const T *fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth)</argsstring>
         <name>awkward_identity_from_listarray</name>
         <param>
@@ -169,9 +169,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/identity.cpp" line="27" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="27" bodyend="45"/>
       </memberdef>
-      <memberdef kind="function" id="identity_8cpp_1a708cbc8cbf2212d7eb81f9e91c1a625c" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_identity32_from_listarray32</definition>
+      <memberdef kind="function" id="identity_8cpp_1acd5da5a40673ec54b9c598f9c863f5a5" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_identity32_from_listarray32</definition>
         <argsstring>(int32_t *toptr, const int32_t *fromptr, const int32_t *fromstarts, const int32_t *fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth)</argsstring>
         <name>awkward_identity32_from_listarray32</name>
         <param>
@@ -222,9 +222,9 @@
         </inbodydescription>
         <location file="src/cpu-kernels/identity.cpp" line="46" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="46" bodyend="48"/>
       </memberdef>
-      <memberdef kind="function" id="identity_8cpp_1afd07f9e094780b2cae299d896b4bf0b8" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_identity64_from_listarray32</definition>
+      <memberdef kind="function" id="identity_8cpp_1ac985473cbcec28806ec563a55fbe2fc4" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_identity64_from_listarray32</definition>
         <argsstring>(int64_t *toptr, const int64_t *fromptr, const int32_t *fromstarts, const int32_t *fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth)</argsstring>
         <name>awkward_identity64_from_listarray32</name>
         <param>
@@ -275,9 +275,62 @@
         </inbodydescription>
         <location file="src/cpu-kernels/identity.cpp" line="49" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="49" bodyend="51"/>
       </memberdef>
-      <memberdef kind="function" id="identity_8cpp_1a87f3652476301a77cb3d42082664dbc1" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
-        <type>Error</type>
-        <definition>Error awkward_identity64_from_listarray64</definition>
+      <memberdef kind="function" id="identity_8cpp_1a3e2d912b77fbceff090cd2022d7e8255" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_identity64_from_listarrayU32</definition>
+        <argsstring>(int64_t *toptr, const int64_t *fromptr, const uint32_t *fromstarts, const uint32_t *fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth)</argsstring>
+        <name>awkward_identity64_from_listarrayU32</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>toptr</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromptr</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>fromptroffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>tolength</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>fromlength</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>fromwidth</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/cpu-kernels/identity.cpp" line="52" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="52" bodyend="54"/>
+      </memberdef>
+      <memberdef kind="function" id="identity_8cpp_1afc1d24571ea0d2a0b31ba58e626f5f4a" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <type>ERROR</type>
+        <definition>ERROR awkward_identity64_from_listarray64</definition>
         <argsstring>(int64_t *toptr, const int64_t *fromptr, const int64_t *fromstarts, const int64_t *fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth)</argsstring>
         <name>awkward_identity64_from_listarray64</name>
         <param>
@@ -326,7 +379,7 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/cpu-kernels/identity.cpp" line="52" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="52" bodyend="54"/>
+        <location file="src/cpu-kernels/identity.cpp" line="55" column="7" bodyfile="src/cpu-kernels/identity.cpp" bodystart="55" bodyend="57"/>
       </memberdef>
       </sectiondef>
     <briefdescription>
diff --git a/awkward1/signatures/libawkward_2util_8cpp.xml b/awkward1/signatures/libawkward_2util_8cpp.xml
index 08ce2c20bb..f917759b77 100644
--- a/awkward1/signatures/libawkward_2util_8cpp.xml
+++ b/awkward1/signatures/libawkward_2util_8cpp.xml
@@ -4,6 +4,8 @@
     <compoundname>util.cpp</compoundname>
     <includes local="no">cassert</includes>
     <includes local="no">sstream</includes>
+    <includes local="yes">awkward/cpu-kernels/identity.h</includes>
+    <includes local="yes">awkward/cpu-kernels/getitem.h</includes>
     <includes local="yes">awkward/util.h</includes>
     <includes local="yes">awkward/Identity.h</includes>
     <incdepgraph>
@@ -18,14 +20,24 @@
         </childnode>
         <childnode refid="5" relation="include">
         </childnode>
+        <childnode refid="6" relation="include">
+        </childnode>
+        <childnode refid="7" relation="include">
+        </childnode>
       </node>
-      <node id="4">
+      <node id="6">
         <label>awkward/util.h</label>
       </node>
       <node id="2">
         <label>cassert</label>
       </node>
       <node id="5">
+        <label>awkward/cpu-kernels/getitem.h</label>
+      </node>
+      <node id="4">
+        <label>awkward/cpu-kernels/identity.h</label>
+      </node>
+      <node id="7">
         <label>awkward/Identity.h</label>
       </node>
       <node id="3">
@@ -35,13 +47,13 @@
     <innernamespace refid="namespaceawkward">awkward</innernamespace>
     <innernamespace refid="namespaceawkward_1_1util">awkward::util</innernamespace>
       <sectiondef kind="func">
-      <memberdef kind="function" id="namespaceawkward_1_1util_1a6abdb46672c5df0d08d26e373626b9dc" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a5cf65ec676d09c60c51f50794ab88153" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
         <type>void</type>
         <definition>void awkward::util::handle_error</definition>
-        <argsstring>(const Error &amp;err, const std::string classname, const Identity *id)</argsstring>
+        <argsstring>(const struct Error &amp;err, const std::string classname, const Identity *id)</argsstring>
         <name>handle_error</name>
         <param>
-          <type>const Error &amp;</type>
+          <type>const struct Error &amp;</type>
           <declname>err</declname>
         </param>
         <param>
@@ -58,7 +70,1245 @@
         </detaileddescription>
         <inbodydescription>
         </inbodydescription>
-        <location file="src/libawkward/util.cpp" line="11" column="10" bodyfile="src/libawkward/util.cpp" bodystart="11" bodyend="30"/>
+        <location file="src/libawkward/util.cpp" line="14" column="10" bodyfile="src/libawkward/util.cpp" bodystart="14" bodyend="33"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a16520ab2a50710adc4155e188d7bd450" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_identity64_from_listarray&lt; uint32_t &gt;</definition>
+        <argsstring>(int64_t *toptr, const int64_t *fromptr, const uint32_t *fromstarts, const uint32_t *fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth)</argsstring>
+        <name>awkward_identity64_from_listarray&lt; uint32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>toptr</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromptr</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>fromptroffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>tolength</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>fromlength</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>fromwidth</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="36" column="5" bodyfile="src/libawkward/util.cpp" bodystart="36" bodyend="38"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a1bd30b78640996660a7ed6083ac8ef27" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_identity64_from_listarray&lt; int64_t &gt;</definition>
+        <argsstring>(int64_t *toptr, const int64_t *fromptr, const int64_t *fromstarts, const int64_t *fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth)</argsstring>
+        <name>awkward_identity64_from_listarray&lt; int64_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>toptr</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromptr</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>fromptroffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>tolength</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>fromlength</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>fromwidth</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="40" column="5" bodyfile="src/libawkward/util.cpp" bodystart="40" bodyend="42"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a35cdf735524b577a33696b6dfbe507c7" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_at_64&lt; int32_t &gt;</definition>
+        <argsstring>(int64_t *tocarry, const int32_t *fromstarts, const int32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at)</argsstring>
+        <name>awkward_listarray_getitem_next_at_64&lt; int32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>at</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="45" column="5" bodyfile="src/libawkward/util.cpp" bodystart="45" bodyend="47"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a332e036036f0a2a7b6ae1ccbd5fb9328" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_at_64&lt; uint32_t &gt;</definition>
+        <argsstring>(int64_t *tocarry, const uint32_t *fromstarts, const uint32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at)</argsstring>
+        <name>awkward_listarray_getitem_next_at_64&lt; uint32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>at</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="49" column="5" bodyfile="src/libawkward/util.cpp" bodystart="49" bodyend="51"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a6669b4753da68138261314266664870f" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_at_64&lt; int64_t &gt;</definition>
+        <argsstring>(int64_t *tocarry, const int64_t *fromstarts, const int64_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at)</argsstring>
+        <name>awkward_listarray_getitem_next_at_64&lt; int64_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>at</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="53" column="5" bodyfile="src/libawkward/util.cpp" bodystart="53" bodyend="55"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1af6d5697f061dd5b2bc6d6371fab63406" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_carrylength&lt; int32_t &gt;</definition>
+        <argsstring>(int64_t *carrylength, const int32_t *fromstarts, const int32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
+        <name>awkward_listarray_getitem_next_range_carrylength&lt; int32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>carrylength</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>start</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stop</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>step</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="58" column="5" bodyfile="src/libawkward/util.cpp" bodystart="58" bodyend="60"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a5994a80cfed68d5ca9a74ec77532eec6" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_carrylength&lt; uint32_t &gt;</definition>
+        <argsstring>(int64_t *carrylength, const uint32_t *fromstarts, const uint32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
+        <name>awkward_listarray_getitem_next_range_carrylength&lt; uint32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>carrylength</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>start</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stop</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>step</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="62" column="5" bodyfile="src/libawkward/util.cpp" bodystart="62" bodyend="64"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1ab91ff6d314c26700c4e4130b6ab4e6b8" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_carrylength&lt; int64_t &gt;</definition>
+        <argsstring>(int64_t *carrylength, const int64_t *fromstarts, const int64_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
+        <name>awkward_listarray_getitem_next_range_carrylength&lt; int64_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>carrylength</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>start</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stop</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>step</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="66" column="5" bodyfile="src/libawkward/util.cpp" bodystart="66" bodyend="68"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1ace2f8fb19c1c5895a11057e5f06ba44a" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_64&lt; int32_t &gt;</definition>
+        <argsstring>(int32_t *tooffsets, int64_t *tocarry, const int32_t *fromstarts, const int32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
+        <name>awkward_listarray_getitem_next_range_64&lt; int32_t &gt;</name>
+        <param>
+          <type>int32_t *</type>
+          <declname>tooffsets</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>start</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stop</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>step</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="71" column="5" bodyfile="src/libawkward/util.cpp" bodystart="71" bodyend="73"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a35f040e2474502f3ebcd72814d81697d" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_64&lt; uint32_t &gt;</definition>
+        <argsstring>(uint32_t *tooffsets, int64_t *tocarry, const uint32_t *fromstarts, const uint32_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
+        <name>awkward_listarray_getitem_next_range_64&lt; uint32_t &gt;</name>
+        <param>
+          <type>uint32_t *</type>
+          <declname>tooffsets</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>start</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stop</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>step</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="75" column="5" bodyfile="src/libawkward/util.cpp" bodystart="75" bodyend="77"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a27301acf05d62d2cddc63402f113186d" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_64&lt; int64_t &gt;</definition>
+        <argsstring>(int64_t *tooffsets, int64_t *tocarry, const int64_t *fromstarts, const int64_t *fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step)</argsstring>
+        <name>awkward_listarray_getitem_next_range_64&lt; int64_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tooffsets</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>start</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stop</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>step</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="79" column="5" bodyfile="src/libawkward/util.cpp" bodystart="79" bodyend="81"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a821d22c5eb2612a50ccd25fad385d50c" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_counts_64&lt; int32_t &gt;</definition>
+        <argsstring>(int64_t *total, const int32_t *fromoffsets, int64_t lenstarts)</argsstring>
+        <name>awkward_listarray_getitem_next_range_counts_64&lt; int32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>total</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromoffsets</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="84" column="5" bodyfile="src/libawkward/util.cpp" bodystart="84" bodyend="86"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1ab7818ea817b037e54c287c5e6209e8a4" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_counts_64&lt; uint32_t &gt;</definition>
+        <argsstring>(int64_t *total, const uint32_t *fromoffsets, int64_t lenstarts)</argsstring>
+        <name>awkward_listarray_getitem_next_range_counts_64&lt; uint32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>total</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromoffsets</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="88" column="5" bodyfile="src/libawkward/util.cpp" bodystart="88" bodyend="90"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1ad129226cfdbe60197ecfef8bb310799d" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_counts_64&lt; int64_t &gt;</definition>
+        <argsstring>(int64_t *total, const int64_t *fromoffsets, int64_t lenstarts)</argsstring>
+        <name>awkward_listarray_getitem_next_range_counts_64&lt; int64_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>total</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromoffsets</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="92" column="5" bodyfile="src/libawkward/util.cpp" bodystart="92" bodyend="94"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a24d53416cb24aeef4b57ca3b206006f0" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_spreadadvanced_64&lt; int32_t &gt;</definition>
+        <argsstring>(int64_t *toadvanced, const int64_t *fromadvanced, const int32_t *fromoffsets, int64_t lenstarts)</argsstring>
+        <name>awkward_listarray_getitem_next_range_spreadadvanced_64&lt; int32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromadvanced</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromoffsets</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="97" column="5" bodyfile="src/libawkward/util.cpp" bodystart="97" bodyend="99"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1ab0ff064b87b541a65ddcba92a1b2292e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_spreadadvanced_64&lt; uint32_t &gt;</definition>
+        <argsstring>(int64_t *toadvanced, const int64_t *fromadvanced, const uint32_t *fromoffsets, int64_t lenstarts)</argsstring>
+        <name>awkward_listarray_getitem_next_range_spreadadvanced_64&lt; uint32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromadvanced</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromoffsets</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="101" column="5" bodyfile="src/libawkward/util.cpp" bodystart="101" bodyend="103"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a55f52d86ee9c4cc0959c9d5123830143" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_range_spreadadvanced_64&lt; int64_t &gt;</definition>
+        <argsstring>(int64_t *toadvanced, const int64_t *fromadvanced, const int64_t *fromoffsets, int64_t lenstarts)</argsstring>
+        <name>awkward_listarray_getitem_next_range_spreadadvanced_64&lt; int64_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromadvanced</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromoffsets</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="105" column="5" bodyfile="src/libawkward/util.cpp" bodystart="105" bodyend="107"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a1b76c1c2e7b0b528979193a823518933" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_array_64&lt; int32_t &gt;</definition>
+        <argsstring>(int32_t *tooffsets, int64_t *tocarry, int64_t *toadvanced, const int32_t *fromstarts, const int32_t *fromstops, const int64_t *fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
+        <name>awkward_listarray_getitem_next_array_64&lt; int32_t &gt;</name>
+        <param>
+          <type>int32_t *</type>
+          <declname>tooffsets</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencontent</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="110" column="5" bodyfile="src/libawkward/util.cpp" bodystart="110" bodyend="112"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a2ebb870b9819f577b067ffc8e0243002" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_array_64&lt; uint32_t &gt;</definition>
+        <argsstring>(uint32_t *tooffsets, int64_t *tocarry, int64_t *toadvanced, const uint32_t *fromstarts, const uint32_t *fromstops, const int64_t *fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
+        <name>awkward_listarray_getitem_next_array_64&lt; uint32_t &gt;</name>
+        <param>
+          <type>uint32_t *</type>
+          <declname>tooffsets</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencontent</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="114" column="5" bodyfile="src/libawkward/util.cpp" bodystart="114" bodyend="116"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a775ff379d676ac0283d26998bf20e13b" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_array_64&lt; int64_t &gt;</definition>
+        <argsstring>(int64_t *tooffsets, int64_t *tocarry, int64_t *toadvanced, const int64_t *fromstarts, const int64_t *fromstops, const int64_t *fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
+        <name>awkward_listarray_getitem_next_array_64&lt; int64_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tooffsets</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencontent</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="118" column="5" bodyfile="src/libawkward/util.cpp" bodystart="118" bodyend="120"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a3c9079e2d6d2eff270b7df911801b07e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_array_advanced_64&lt; int32_t &gt;</definition>
+        <argsstring>(int64_t *tocarry, int64_t *toadvanced, const int32_t *fromstarts, const int32_t *fromstops, const int64_t *fromarray, const int64_t *fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
+        <name>awkward_listarray_getitem_next_array_advanced_64&lt; int32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromarray</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromadvanced</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencontent</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="123" column="5" bodyfile="src/libawkward/util.cpp" bodystart="123" bodyend="125"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a0a5ce7851259ae74844da07ed068ab7e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_array_advanced_64&lt; uint32_t &gt;</definition>
+        <argsstring>(int64_t *tocarry, int64_t *toadvanced, const uint32_t *fromstarts, const uint32_t *fromstops, const int64_t *fromarray, const int64_t *fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
+        <name>awkward_listarray_getitem_next_array_advanced_64&lt; uint32_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromarray</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromadvanced</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencontent</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="127" column="5" bodyfile="src/libawkward/util.cpp" bodystart="127" bodyend="129"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a3853c79e8dfd566edb8c1c2affc70934" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_next_array_advanced_64&lt; int64_t &gt;</definition>
+        <argsstring>(int64_t *tocarry, int64_t *toadvanced, const int64_t *fromstarts, const int64_t *fromstops, const int64_t *fromarray, const int64_t *fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent)</argsstring>
+        <name>awkward_listarray_getitem_next_array_advanced_64&lt; int64_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tocarry</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>toadvanced</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromarray</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromadvanced</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenarray</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencontent</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="131" column="5" bodyfile="src/libawkward/util.cpp" bodystart="131" bodyend="133"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a56c8f0daa473f11d34e367c7f6d7100e" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_carry_64&lt; int32_t &gt;</definition>
+        <argsstring>(int32_t *tostarts, int32_t *tostops, const int32_t *fromstarts, const int32_t *fromstops, const int64_t *fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry)</argsstring>
+        <name>awkward_listarray_getitem_carry_64&lt; int32_t &gt;</name>
+        <param>
+          <type>int32_t *</type>
+          <declname>tostarts</declname>
+        </param>
+        <param>
+          <type>int32_t *</type>
+          <declname>tostops</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromcarry</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencarry</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="136" column="5" bodyfile="src/libawkward/util.cpp" bodystart="136" bodyend="138"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1ab998cec0a24c51454bdf93e04ee173a3" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_carry_64&lt; uint32_t &gt;</definition>
+        <argsstring>(uint32_t *tostarts, uint32_t *tostops, const uint32_t *fromstarts, const uint32_t *fromstops, const int64_t *fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry)</argsstring>
+        <name>awkward_listarray_getitem_carry_64&lt; uint32_t &gt;</name>
+        <param>
+          <type>uint32_t *</type>
+          <declname>tostarts</declname>
+        </param>
+        <param>
+          <type>uint32_t *</type>
+          <declname>tostops</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const uint32_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromcarry</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencarry</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="140" column="5" bodyfile="src/libawkward/util.cpp" bodystart="140" bodyend="142"/>
+      </memberdef>
+      <memberdef kind="function" id="namespaceawkward_1_1util_1a02e137f16fe72a0671a42b43cc5bb543" prot="public" static="no" const="no" explicit="no" inline="no" virt="non-virtual">
+        <templateparamlist>
+        </templateparamlist>
+        <type>Error</type>
+        <definition>Error awkward::util::awkward_listarray_getitem_carry_64&lt; int64_t &gt;</definition>
+        <argsstring>(int64_t *tostarts, int64_t *tostops, const int64_t *fromstarts, const int64_t *fromstops, const int64_t *fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry)</argsstring>
+        <name>awkward_listarray_getitem_carry_64&lt; int64_t &gt;</name>
+        <param>
+          <type>int64_t *</type>
+          <declname>tostarts</declname>
+        </param>
+        <param>
+          <type>int64_t *</type>
+          <declname>tostops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstarts</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromstops</declname>
+        </param>
+        <param>
+          <type>const int64_t *</type>
+          <declname>fromcarry</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>startsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>stopsoffset</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lenstarts</declname>
+        </param>
+        <param>
+          <type>int64_t</type>
+          <declname>lencarry</declname>
+        </param>
+        <briefdescription>
+        </briefdescription>
+        <detaileddescription>
+        </detaileddescription>
+        <inbodydescription>
+        </inbodydescription>
+        <location file="src/libawkward/util.cpp" line="144" column="5" bodyfile="src/libawkward/util.cpp" bodystart="144" bodyend="146"/>
       </memberdef>
       </sectiondef>
     <briefdescription>
diff --git a/include/awkward/Index.h b/include/awkward/Index.h
index 8b740e84af..9c69e79937 100644
--- a/include/awkward/Index.h
+++ b/include/awkward/Index.h
@@ -46,9 +46,11 @@ namespace awkward {
     const int64_t length_;
   };
 
-  typedef IndexOf<int8_t>  Index8;
-  typedef IndexOf<int32_t> Index32;
-  typedef IndexOf<int64_t> Index64;
+  typedef IndexOf<int8_t>   Index8;
+  typedef IndexOf<uint8_t>  IndexU8;
+  typedef IndexOf<int32_t>  Index32;
+  typedef IndexOf<uint32_t> IndexU32;
+  typedef IndexOf<int64_t>  Index64;
 }
 
 #endif // AWKWARD_INDEX_H_
diff --git a/include/awkward/array/ListArray.h b/include/awkward/array/ListArray.h
index b5d9ac92fc..f2cac9a424 100644
--- a/include/awkward/array/ListArray.h
+++ b/include/awkward/array/ListArray.h
@@ -48,8 +48,9 @@ namespace awkward {
     const std::shared_ptr<Content> content_;
   };
 
-  typedef ListArrayOf<int32_t> ListArray32;
-  typedef ListArrayOf<int64_t> ListArray64;
+  typedef ListArrayOf<int32_t>  ListArray32;
+  typedef ListArrayOf<uint32_t> ListArrayU32;
+  typedef ListArrayOf<int64_t>  ListArray64;
 }
 
 #endif // AWKWARD_LISTARRAY_H_
diff --git a/include/awkward/array/ListOffsetArray.h b/include/awkward/array/ListOffsetArray.h
index f09b7cf8a6..48037b314f 100644
--- a/include/awkward/array/ListOffsetArray.h
+++ b/include/awkward/array/ListOffsetArray.h
@@ -45,8 +45,9 @@ namespace awkward {
     const std::shared_ptr<Content> content_;
   };
 
-  typedef ListOffsetArrayOf<int32_t> ListOffsetArray32;
-  typedef ListOffsetArrayOf<int64_t> ListOffsetArray64;
+  typedef ListOffsetArrayOf<int32_t>  ListOffsetArray32;
+  typedef ListOffsetArrayOf<uint32_t> ListOffsetArrayU32;
+  typedef ListOffsetArrayOf<int64_t>  ListOffsetArray64;
 }
 
 #endif // AWKWARD_LISTOFFSETARRAY_H_
diff --git a/include/awkward/cpu-kernels/getitem.h b/include/awkward/cpu-kernels/getitem.h
index 4f9dcf9ffa..95ed22f232 100644
--- a/include/awkward/cpu-kernels/getitem.h
+++ b/include/awkward/cpu-kernels/getitem.h
@@ -28,27 +28,35 @@ extern "C" {
   struct Error awkward_numpyarray_getitem_next_array_advanced_64(int64_t* nextcarryptr, const int64_t* carryptr, const int64_t* advancedptr, const int64_t* flatheadptr, int64_t lencarry, int64_t skip);
 
   struct Error awkward_listarray32_getitem_next_at_64(int64_t* tocarry, const int32_t* fromstarts, const int32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at);
+  struct Error awkward_listarrayU32_getitem_next_at_64(int64_t* tocarry, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at);
   struct Error awkward_listarray64_getitem_next_at_64(int64_t* tocarry, const int64_t* fromstarts, const int64_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at);
 
   struct Error awkward_listarray32_getitem_next_range_carrylength(int64_t* carrylength, const int32_t* fromstarts, const int32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step);
+  struct Error awkward_listarrayU32_getitem_next_range_carrylength(int64_t* carrylength, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step);
   struct Error awkward_listarray64_getitem_next_range_carrylength(int64_t* carrylength, const int64_t* fromstarts, const int64_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step);
 
   struct Error awkward_listarray32_getitem_next_range_64(int32_t* tooffsets, int64_t* tocarry, const int32_t* fromstarts, const int32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step);
+  struct Error awkward_listarrayU32_getitem_next_range_64(uint32_t* tooffsets, int64_t* tocarry, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step);
   struct Error awkward_listarray64_getitem_next_range_64(int64_t* tooffsets, int64_t* tocarry, const int64_t* fromstarts, const int64_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step);
 
   struct Error awkward_listarray32_getitem_next_range_counts_64(int64_t* total, const int32_t* fromoffsets, int64_t lenstarts);
+  struct Error awkward_listarrayU32_getitem_next_range_counts_64(int64_t* total, const uint32_t* fromoffsets, int64_t lenstarts);
   struct Error awkward_listarray64_getitem_next_range_counts_64(int64_t* total, const int64_t* fromoffsets, int64_t lenstarts);
 
   struct Error awkward_listarray32_getitem_next_range_spreadadvanced_64(int64_t* toadvanced, const int64_t* fromadvanced, const int32_t* fromoffsets, int64_t lenstarts);
+  struct Error awkward_listarrayU32_getitem_next_range_spreadadvanced_64(int64_t* toadvanced, const int64_t* fromadvanced, const uint32_t* fromoffsets, int64_t lenstarts);
   struct Error awkward_listarray64_getitem_next_range_spreadadvanced_64(int64_t* toadvanced, const int64_t* fromadvanced, const int64_t* fromoffsets, int64_t lenstarts);
 
   struct Error awkward_listarray32_getitem_next_array_64(int32_t* tooffsets, int64_t* tocarry, int64_t* toadvanced, const int32_t* fromstarts, const int32_t* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent);
+  struct Error awkward_listarrayU32_getitem_next_array_64(uint32_t* tooffsets, int64_t* tocarry, int64_t* toadvanced, const uint32_t* fromstarts, const uint32_t* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent);
   struct Error awkward_listarray64_getitem_next_array_64(int64_t* tooffsets, int64_t* tocarry, int64_t* toadvanced, const int64_t* fromstarts, const int64_t* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent);
 
   struct Error awkward_listarray32_getitem_next_array_advanced_64(int64_t* tocarry, int64_t* toadvanced, const int32_t* fromstarts, const int32_t* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent);
+  struct Error awkward_listarrayU32_getitem_next_array_advanced_64(int64_t* tocarry, int64_t* toadvanced, const uint32_t* fromstarts, const uint32_t* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent);
   struct Error awkward_listarray64_getitem_next_array_advanced_64(int64_t* tocarry, int64_t* toadvanced, const int64_t* fromstarts, const int64_t* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent);
 
   struct Error awkward_listarray32_getitem_carry_64(int32_t* tostarts, int32_t* tostops, const int32_t* fromstarts, const int32_t* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry);
+  struct Error awkward_listarrayU32_getitem_carry_64(uint32_t* tostarts, uint32_t* tostops, const uint32_t* fromstarts, const uint32_t* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry);
   struct Error awkward_listarray64_getitem_carry_64(int64_t* tostarts, int64_t* tostops, const int64_t* fromstarts, const int64_t* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry);
 }
 
diff --git a/include/awkward/cpu-kernels/identity.h b/include/awkward/cpu-kernels/identity.h
index c6c8506306..25d9ed0276 100644
--- a/include/awkward/cpu-kernels/identity.h
+++ b/include/awkward/cpu-kernels/identity.h
@@ -13,6 +13,7 @@ extern "C" {
 
   struct Error awkward_identity32_from_listarray32(int32_t* toptr, const int32_t* fromptr, const int32_t* fromstarts, const int32_t* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth);
   struct Error awkward_identity64_from_listarray32(int64_t* toptr, const int64_t* fromptr, const int32_t* fromstarts, const int32_t* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth);
+  struct Error awkward_identity64_from_listarrayU32(int64_t* toptr, const int64_t* fromptr, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth);
   struct Error awkward_identity64_from_listarray64(int64_t* toptr, const int64_t* fromptr, const int64_t* fromstarts, const int64_t* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth);
 }
 
diff --git a/include/awkward/cpu-kernels/util.h b/include/awkward/cpu-kernels/util.h
index efc1cc5d79..33325b001b 100644
--- a/include/awkward/cpu-kernels/util.h
+++ b/include/awkward/cpu-kernels/util.h
@@ -38,11 +38,12 @@ extern "C" {
   struct Error success();
   struct Error failure(const char* str, int64_t location, int64_t attempt);
 
-  const int8_t  kMaxInt8   =                 127;   // 2**7  - 1
-  const uint8_t kMaxUInt8  =                 255;   // 2**8  - 1
-  const int32_t kMaxInt32  =          2147483647;   // 2**31 - 1
-  const int64_t kMaxInt64  = 9223372036854775806;   // 2**63 - 2: see below
-  const int64_t kSliceNone = kMaxInt64 + 1;         // reserved for Slice::none()
+  const int8_t   kMaxInt8   =                 127;   // 2**7  - 1
+  const uint8_t  kMaxUInt8  =                 255;   // 2**8  - 1
+  const int32_t  kMaxInt32  =          2147483647;   // 2**31 - 1
+  const uint32_t kMaxUInt32 =          4294967295;   // 2**32 - 1
+  const int64_t  kMaxInt64  = 9223372036854775806;   // 2**63 - 2: see below
+  const int64_t  kSliceNone = kMaxInt64 + 1;         // reserved for Slice::none()
 }
 
 #endif // AWKWARDCPU_UTIL_H_
diff --git a/include/awkward/util.h b/include/awkward/util.h
index 03959bb5ba..77030bc032 100644
--- a/include/awkward/util.h
+++ b/include/awkward/util.h
@@ -26,6 +26,26 @@ namespace awkward {
     public:
       void operator()(T const *p) { }
     };
+
+    template <typename T>
+    Error awkward_identity64_from_listarray(int64_t* toptr, const int64_t* fromptr, const T* fromstarts, const T* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth);
+    template <typename T>
+    Error awkward_listarray_getitem_next_at_64(int64_t* tocarry, const T* fromstarts, const T* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at);
+    template <typename T>
+    Error awkward_listarray_getitem_next_range_carrylength(int64_t* carrylength, const T* fromstarts, const T* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step);
+    template <typename T>
+    Error awkward_listarray_getitem_next_range_64(T* tooffsets, int64_t* tocarry, const T* fromstarts, const T* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step);
+    template <typename T>
+    Error awkward_listarray_getitem_next_range_counts_64(int64_t* total, const T* fromoffsets, int64_t lenstarts);
+    template <typename T>
+    Error awkward_listarray_getitem_next_range_spreadadvanced_64(int64_t* toadvanced, const int64_t* fromadvanced, const T* fromoffsets, int64_t lenstarts);
+    template <typename T>
+    Error awkward_listarray_getitem_next_array_64(T* tooffsets, int64_t* tocarry, int64_t* toadvanced, const T* fromstarts, const T* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent);
+    template <typename T>
+    Error awkward_listarray_getitem_next_array_advanced_64(int64_t* tocarry, int64_t* toadvanced, const T* fromstarts, const T* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent);
+    template <typename T>
+    Error awkward_listarray_getitem_carry_64(T* tostarts, T* tostops, const T* fromstarts, const T* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry);
+
   }
 }
 
diff --git a/src/cpu-kernels/getitem.cpp b/src/cpu-kernels/getitem.cpp
index e33e38665c..0141cb17e2 100644
--- a/src/cpu-kernels/getitem.cpp
+++ b/src/cpu-kernels/getitem.cpp
@@ -227,6 +227,9 @@ ERROR awkward_listarray_getitem_next_at(T* tocarry, const C* fromstarts, const C
 ERROR awkward_listarray32_getitem_next_at_64(int64_t* tocarry, const int32_t* fromstarts, const int32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at) {
   return awkward_listarray_getitem_next_at<int32_t, int64_t>(tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, at);
 }
+ERROR awkward_listarrayU32_getitem_next_at_64(int64_t* tocarry, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at) {
+  return awkward_listarray_getitem_next_at<uint32_t, int64_t>(tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, at);
+}
 ERROR awkward_listarray64_getitem_next_at_64(int64_t* tocarry, const int64_t* fromstarts, const int64_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at) {
   return awkward_listarray_getitem_next_at<int64_t, int64_t>(tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, at);
 }
@@ -255,6 +258,9 @@ ERROR awkward_listarray_getitem_next_range_carrylength(int64_t* carrylength, con
 ERROR awkward_listarray32_getitem_next_range_carrylength(int64_t* carrylength, const int32_t* fromstarts, const int32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
   return awkward_listarray_getitem_next_range_carrylength<int32_t>(carrylength, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
 }
+ERROR awkward_listarrayU32_getitem_next_range_carrylength(int64_t* carrylength, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
+  return awkward_listarray_getitem_next_range_carrylength<uint32_t>(carrylength, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
+}
 ERROR awkward_listarray64_getitem_next_range_carrylength(int64_t* carrylength, const int64_t* fromstarts, const int64_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
   return awkward_listarray_getitem_next_range_carrylength<int64_t>(carrylength, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
 }
@@ -287,6 +293,9 @@ ERROR awkward_listarray_getitem_next_range(C* tooffsets, T* tocarry, const C* fr
 ERROR awkward_listarray32_getitem_next_range_64(int32_t* tooffsets, int64_t* tocarry, const int32_t* fromstarts, const int32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
   return awkward_listarray_getitem_next_range<int32_t, int64_t>(tooffsets, tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
 }
+ERROR awkward_listarrayU32_getitem_next_range_64(uint32_t* tooffsets, int64_t* tocarry, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
+  return awkward_listarray_getitem_next_range<uint32_t, int64_t>(tooffsets, tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
+}
 ERROR awkward_listarray64_getitem_next_range_64(int64_t* tooffsets, int64_t* tocarry, const int64_t* fromstarts, const int64_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
   return awkward_listarray_getitem_next_range<int64_t, int64_t>(tooffsets, tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
 }
@@ -302,6 +311,9 @@ ERROR awkward_listarray_getitem_next_range_counts(int64_t* total, const C* fromo
 ERROR awkward_listarray32_getitem_next_range_counts_64(int64_t* total, const int32_t* fromoffsets, int64_t lenstarts) {
   return awkward_listarray_getitem_next_range_counts<int32_t, int64_t>(total, fromoffsets, lenstarts);
 }
+ERROR awkward_listarrayU32_getitem_next_range_counts_64(int64_t* total, const uint32_t* fromoffsets, int64_t lenstarts) {
+  return awkward_listarray_getitem_next_range_counts<uint32_t, int64_t>(total, fromoffsets, lenstarts);
+}
 ERROR awkward_listarray64_getitem_next_range_counts_64(int64_t* total, const int64_t* fromoffsets, int64_t lenstarts) {
   return awkward_listarray_getitem_next_range_counts<int64_t, int64_t>(total, fromoffsets, lenstarts);
 }
@@ -319,6 +331,9 @@ ERROR awkward_listarray_getitem_next_range_spreadadvanced(T* toadvanced, const T
 ERROR awkward_listarray32_getitem_next_range_spreadadvanced_64(int64_t* toadvanced, const int64_t* fromadvanced, const int32_t* fromoffsets, int64_t lenstarts) {
   return awkward_listarray_getitem_next_range_spreadadvanced<int32_t, int64_t>(toadvanced, fromadvanced, fromoffsets, lenstarts);
 }
+ERROR awkward_listarrayU32_getitem_next_range_spreadadvanced_64(int64_t* toadvanced, const int64_t* fromadvanced, const uint32_t* fromoffsets, int64_t lenstarts) {
+  return awkward_listarray_getitem_next_range_spreadadvanced<uint32_t, int64_t>(toadvanced, fromadvanced, fromoffsets, lenstarts);
+}
 ERROR awkward_listarray64_getitem_next_range_spreadadvanced_64(int64_t* toadvanced, const int64_t* fromadvanced, const int64_t* fromoffsets, int64_t lenstarts) {
   return awkward_listarray_getitem_next_range_spreadadvanced<int64_t, int64_t>(toadvanced, fromadvanced, fromoffsets, lenstarts);
 }
@@ -352,6 +367,9 @@ ERROR awkward_listarray_getitem_next_array(C* tooffsets, T* tocarry, T* toadvanc
 ERROR awkward_listarray32_getitem_next_array_64(int32_t* tooffsets, int64_t* tocarry, int64_t* toadvanced, const int32_t* fromstarts, const int32_t* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
   return awkward_listarray_getitem_next_array<int32_t, int64_t>(tooffsets, tocarry, toadvanced, fromstarts, fromstops, fromarray, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
 }
+ERROR awkward_listarrayU32_getitem_next_array_64(uint32_t* tooffsets, int64_t* tocarry, int64_t* toadvanced, const uint32_t* fromstarts, const uint32_t* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
+  return awkward_listarray_getitem_next_array<uint32_t, int64_t>(tooffsets, tocarry, toadvanced, fromstarts, fromstops, fromarray, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
+}
 ERROR awkward_listarray64_getitem_next_array_64(int64_t* tooffsets, int64_t* tocarry, int64_t* toadvanced, const int64_t* fromstarts, const int64_t* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
   return awkward_listarray_getitem_next_array<int64_t, int64_t>(tooffsets, tocarry, toadvanced, fromstarts, fromstops, fromarray, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
 }
@@ -384,6 +402,9 @@ ERROR awkward_listarray_getitem_next_array_advanced(T* tocarry, T* toadvanced, c
 ERROR awkward_listarray32_getitem_next_array_advanced_64(int64_t* tocarry, int64_t* toadvanced, const int32_t* fromstarts, const int32_t* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
   return awkward_listarray_getitem_next_array_advanced<int32_t, int64_t>(tocarry, toadvanced, fromstarts, fromstops, fromarray, fromadvanced, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
 }
+ERROR awkward_listarrayU32_getitem_next_array_advanced_64(int64_t* tocarry, int64_t* toadvanced, const uint32_t* fromstarts, const uint32_t* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
+  return awkward_listarray_getitem_next_array_advanced<uint32_t, int64_t>(tocarry, toadvanced, fromstarts, fromstops, fromarray, fromadvanced, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
+}
 ERROR awkward_listarray64_getitem_next_array_advanced_64(int64_t* tocarry, int64_t* toadvanced, const int64_t* fromstarts, const int64_t* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
   return awkward_listarray_getitem_next_array_advanced<int64_t, int64_t>(tocarry, toadvanced, fromstarts, fromstops, fromarray, fromadvanced, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
 }
@@ -402,6 +423,9 @@ ERROR awkward_listarray_getitem_carry(C* tostarts, C* tostops, const C* fromstar
 ERROR awkward_listarray32_getitem_carry_64(int32_t* tostarts, int32_t* tostops, const int32_t* fromstarts, const int32_t* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry) {
   return awkward_listarray_getitem_carry<int32_t, int64_t>(tostarts, tostops, fromstarts, fromstops, fromcarry, startsoffset, stopsoffset, lenstarts, lencarry);
 }
+ERROR awkward_listarrayU32_getitem_carry_64(uint32_t* tostarts, uint32_t* tostops, const uint32_t* fromstarts, const uint32_t* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry) {
+  return awkward_listarray_getitem_carry<uint32_t, int64_t>(tostarts, tostops, fromstarts, fromstops, fromcarry, startsoffset, stopsoffset, lenstarts, lencarry);
+}
 ERROR awkward_listarray64_getitem_carry_64(int64_t* tostarts, int64_t* tostops, const int64_t* fromstarts, const int64_t* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry) {
   return awkward_listarray_getitem_carry<int64_t, int64_t>(tostarts, tostops, fromstarts, fromstops, fromcarry, startsoffset, stopsoffset, lenstarts, lencarry);
 }
diff --git a/src/cpu-kernels/identity.cpp b/src/cpu-kernels/identity.cpp
index a74c4e4ff2..4292442da1 100644
--- a/src/cpu-kernels/identity.cpp
+++ b/src/cpu-kernels/identity.cpp
@@ -49,6 +49,9 @@ ERROR awkward_identity32_from_listarray32(int32_t* toptr, const int32_t* fromptr
 ERROR awkward_identity64_from_listarray32(int64_t* toptr, const int64_t* fromptr, const int32_t* fromstarts, const int32_t* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth) {
   return awkward_identity_from_listarray<int64_t, int32_t>(toptr, fromptr, fromstarts, fromstops, fromptroffset, startsoffset, stopsoffset, tolength, fromlength, fromwidth);
 }
+ERROR awkward_identity64_from_listarrayU32(int64_t* toptr, const int64_t* fromptr, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth) {
+  return awkward_identity_from_listarray<int64_t, uint32_t>(toptr, fromptr, fromstarts, fromstops, fromptroffset, startsoffset, stopsoffset, tolength, fromlength, fromwidth);
+}
 ERROR awkward_identity64_from_listarray64(int64_t* toptr, const int64_t* fromptr, const int64_t* fromstarts, const int64_t* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth) {
   return awkward_identity_from_listarray<int64_t, int64_t>(toptr, fromptr, fromstarts, fromstops, fromptroffset, startsoffset, stopsoffset, tolength, fromlength, fromwidth);
 }
diff --git a/src/libawkward/Index.cpp b/src/libawkward/Index.cpp
index 0c8d10600e..4cc76051b8 100644
--- a/src/libawkward/Index.cpp
+++ b/src/libawkward/Index.cpp
@@ -11,12 +11,18 @@
 namespace awkward {
   template <typename T>
   const std::string IndexOf<T>::classname() const {
-    if (std::is_same<T, uint8_t>::value) {
+    if (std::is_same<T, int8_t>::value) {
       return "Index8";
     }
+    else if (std::is_same<T, uint8_t>::value) {
+      return "IndexU8";
+    }
     else if (std::is_same<T, int32_t>::value) {
       return "Index32";
     }
+    else if (std::is_same<T, uint32_t>::value) {
+      return "IndexU32";
+    }
     else if (std::is_same<T, int64_t>::value) {
       return "Index64";
     }
@@ -106,6 +112,8 @@ namespace awkward {
   }
 
   template class IndexOf<int8_t>;
+  template class IndexOf<uint8_t>;
   template class IndexOf<int32_t>;
+  template class IndexOf<uint32_t>;
   template class IndexOf<int64_t>;
 }
diff --git a/src/libawkward/array/ListArray.cpp b/src/libawkward/array/ListArray.cpp
index 445cb83689..d8ba03e5d2 100644
--- a/src/libawkward/array/ListArray.cpp
+++ b/src/libawkward/array/ListArray.cpp
@@ -16,6 +16,9 @@ namespace awkward {
     if (std::is_same<T, int32_t>::value) {
       return "ListArray32";
     }
+    else if (std::is_same<T, uint32_t>::value) {
+      return "ListArrayU32";
+    }
     else if (std::is_same<T, int64_t>::value) {
       return "ListArray64";
     }
@@ -78,8 +81,8 @@ namespace awkward {
     id_ = id;
   }
 
-  template <>
-  void ListArrayOf<int64_t>::setid(const std::shared_ptr<Identity> id) {
+  template <typename T>
+  void ListArrayOf<T>::setid(const std::shared_ptr<Identity> id) {
     if (id.get() == nullptr) {
       content_.get()->setid(id);
     }
@@ -91,7 +94,7 @@ namespace awkward {
       if (Identity64* rawid = dynamic_cast<Identity64*>(bigid.get())) {
         Identity64* rawsubid = new Identity64(Identity::newref(), rawid->fieldloc(), rawid->width() + 1, content_.get()->length());
         std::shared_ptr<Identity> subid(rawsubid);
-        struct Error err = awkward_identity64_from_listarray64(
+        struct Error err = util::awkward_identity64_from_listarray<T>(
           rawsubid->ptr().get(),
           rawid->ptr().get(),
           starts_.ptr().get(),
@@ -225,156 +228,8 @@ namespace awkward {
     return std::shared_ptr<Content>(new ListArrayOf<T>(id, starts_.getitem_range_unsafe(start, stop), stops_.getitem_range_unsafe(start, stop), content_));
   }
 
-  template <>
-  const std::shared_ptr<Content> ListArrayOf<int32_t>::getitem_next(const std::shared_ptr<SliceItem> head, const Slice& tail, const Index64& advanced) const {
-    int64_t lenstarts = starts_.length();
-    if (stops_.length() < lenstarts) {
-      util::handle_error(failure("len(stops) < len(starts)", kSliceNone, kSliceNone), classname(), id_.get());
-    }
-
-    if (head.get() == nullptr) {
-      return shallow_copy();
-    }
-
-    else if (SliceAt* at = dynamic_cast<SliceAt*>(head.get())) {
-      assert(advanced.length() == 0);
-      std::shared_ptr<SliceItem> nexthead = tail.head();
-      Slice nexttail = tail.tail();
-      Index64 nextcarry(lenstarts);
-      struct Error err = awkward_listarray32_getitem_next_at_64(
-        nextcarry.ptr().get(),
-        starts_.ptr().get(),
-        stops_.ptr().get(),
-        lenstarts,
-        starts_.offset(),
-        stops_.offset(),
-        at->at());
-      util::handle_error(err, classname(), id_.get());
-      std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
-      return nextcontent.get()->getitem_next(nexthead, nexttail, advanced);
-    }
-
-    else if (SliceRange* range = dynamic_cast<SliceRange*>(head.get())) {
-      std::shared_ptr<SliceItem> nexthead = tail.head();
-      Slice nexttail = tail.tail();
-      int64_t start = range->start();
-      int64_t stop = range->stop();
-      int64_t step = range->step();
-      if (step == Slice::none()) {
-        step = 1;
-      }
-      int64_t carrylength;
-      struct Error err1 = awkward_listarray32_getitem_next_range_carrylength(
-        &carrylength,
-        starts_.ptr().get(),
-        stops_.ptr().get(),
-        lenstarts,
-        starts_.offset(),
-        stops_.offset(),
-        start,
-        stop,
-        step);
-      util::handle_error(err1, classname(), id_.get());
-
-      Index32 nextoffsets(lenstarts + 1);
-      Index64 nextcarry(carrylength);
-
-      struct Error err2 = awkward_listarray32_getitem_next_range_64(
-        nextoffsets.ptr().get(),
-        nextcarry.ptr().get(),
-        starts_.ptr().get(),
-        stops_.ptr().get(),
-        lenstarts,
-        starts_.offset(),
-        stops_.offset(),
-        start,
-        stop,
-        step);
-      util::handle_error(err2, classname(), id_.get());
-      std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
-
-      if (advanced.length() == 0) {
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int32_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, advanced)));
-      }
-      else {
-        int64_t total;
-        struct Error err1 = awkward_listarray32_getitem_next_range_counts_64(
-          &total,
-          nextoffsets.ptr().get(),
-          lenstarts);
-        util::handle_error(err1, classname(), id_.get());
-        Index64 nextadvanced(total);
-        struct Error err2 = awkward_listarray32_getitem_next_range_spreadadvanced_64(
-          nextadvanced.ptr().get(),
-          advanced.ptr().get(),
-          nextoffsets.ptr().get(),
-          lenstarts);
-        util::handle_error(err2, classname(), id_.get());
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int32_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
-      }
-    }
-
-    else if (SliceEllipsis* ellipsis = dynamic_cast<SliceEllipsis*>(head.get())) {
-      return getitem_ellipsis(tail, advanced);
-    }
-
-    else if (SliceNewAxis* newaxis = dynamic_cast<SliceNewAxis*>(head.get())) {
-      return getitem_newaxis(tail, advanced);
-    }
-
-    else if (SliceArray64* array = dynamic_cast<SliceArray64*>(head.get())) {
-      std::shared_ptr<SliceItem> nexthead = tail.head();
-      Slice nexttail = tail.tail();
-      Index64 flathead = array->ravel();
-      if (advanced.length() == 0) {
-        Index64 nextcarry(lenstarts*flathead.length());
-        Index64 nextadvanced(lenstarts*flathead.length());
-        Index32 nextoffsets(lenstarts + 1);
-        struct Error err = awkward_listarray32_getitem_next_array_64(
-          nextoffsets.ptr().get(),
-          nextcarry.ptr().get(),
-          nextadvanced.ptr().get(),
-          starts_.ptr().get(),
-          stops_.ptr().get(),
-          flathead.ptr().get(),
-          starts_.offset(),
-          stops_.offset(),
-          lenstarts,
-          flathead.length(),
-          content_.get()->length());
-        util::handle_error(err, classname(), id_.get());
-        std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
-        // FIXME: if the head is not flat, you'll need to wrap the ListArray output in a RegularArray
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int32_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
-      }
-      else {
-        Index64 nextcarry(lenstarts);
-        Index64 nextadvanced(lenstarts);
-        struct Error err = awkward_listarray32_getitem_next_array_advanced_64(
-          nextcarry.ptr().get(),
-          nextadvanced.ptr().get(),
-          starts_.ptr().get(),
-          stops_.ptr().get(),
-          flathead.ptr().get(),
-          advanced.ptr().get(),
-          starts_.offset(),
-          stops_.offset(),
-          lenstarts,
-          flathead.length(),
-          content_.get()->length());
-        util::handle_error(err, classname(), id_.get());
-        std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
-        return nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced);
-      }
-    }
-
-    else {
-      throw std::runtime_error("unrecognized slice item type");
-    }
-  }
-
-  template <>
-  const std::shared_ptr<Content> ListArrayOf<int64_t>::getitem_next(const std::shared_ptr<SliceItem> head, const Slice& tail, const Index64& advanced) const {
+  template <typename T>
+  const std::shared_ptr<Content> ListArrayOf<T>::getitem_next(const std::shared_ptr<SliceItem> head, const Slice& tail, const Index64& advanced) const {
     int64_t lenstarts = starts_.length();
     if (stops_.length() < lenstarts) {
       util::handle_error(failure("len(stops) < len(starts)", kSliceNone, kSliceNone), classname(), id_.get());
@@ -389,7 +244,7 @@ namespace awkward {
       std::shared_ptr<SliceItem> nexthead = tail.head();
       Slice nexttail = tail.tail();
       Index64 nextcarry(lenstarts);
-      struct Error err = awkward_listarray64_getitem_next_at_64(
+      struct Error err = util::awkward_listarray_getitem_next_at_64<T>(
         nextcarry.ptr().get(),
         starts_.ptr().get(),
         stops_.ptr().get(),
@@ -412,7 +267,7 @@ namespace awkward {
         step = 1;
       }
       int64_t carrylength;
-      struct Error err1 = awkward_listarray64_getitem_next_range_carrylength(
+      struct Error err1 = util::awkward_listarray_getitem_next_range_carrylength<T>(
         &carrylength,
         starts_.ptr().get(),
         stops_.ptr().get(),
@@ -424,10 +279,10 @@ namespace awkward {
         step);
       util::handle_error(err1, classname(), id_.get());
 
-      Index64 nextoffsets(lenstarts + 1);
+      IndexOf<T> nextoffsets(lenstarts + 1);
       Index64 nextcarry(carrylength);
 
-      struct Error err2 = awkward_listarray64_getitem_next_range_64(
+      struct Error err2 = util::awkward_listarray_getitem_next_range_64<T>(
         nextoffsets.ptr().get(),
         nextcarry.ptr().get(),
         starts_.ptr().get(),
@@ -442,23 +297,23 @@ namespace awkward {
       std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
 
       if (advanced.length() == 0) {
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int64_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, advanced)));
+        return std::shared_ptr<Content>(new ListOffsetArrayOf<T>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, advanced)));
       }
       else {
         int64_t total;
-        struct Error err1 = awkward_listarray64_getitem_next_range_counts_64(
+        struct Error err1 = util::awkward_listarray_getitem_next_range_counts_64<T>(
           &total,
           nextoffsets.ptr().get(),
           lenstarts);
         util::handle_error(err1, classname(), id_.get());
         Index64 nextadvanced(total);
-        struct Error err2 = awkward_listarray64_getitem_next_range_spreadadvanced_64(
+        struct Error err2 = util::awkward_listarray_getitem_next_range_spreadadvanced_64<T>(
           nextadvanced.ptr().get(),
           advanced.ptr().get(),
           nextoffsets.ptr().get(),
           lenstarts);
         util::handle_error(err2, classname(), id_.get());
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int64_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
+        return std::shared_ptr<Content>(new ListOffsetArrayOf<T>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
       }
     }
 
@@ -477,8 +332,8 @@ namespace awkward {
       if (advanced.length() == 0) {
         Index64 nextcarry(lenstarts*flathead.length());
         Index64 nextadvanced(lenstarts*flathead.length());
-        Index64 nextoffsets(lenstarts + 1);
-        struct Error err = awkward_listarray64_getitem_next_array_64(
+        IndexOf<T> nextoffsets(lenstarts + 1);
+        struct Error err = util::awkward_listarray_getitem_next_array_64<T>(
           nextoffsets.ptr().get(),
           nextcarry.ptr().get(),
           nextadvanced.ptr().get(),
@@ -493,12 +348,12 @@ namespace awkward {
         util::handle_error(err, classname(), id_.get());
         std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
         // FIXME: if the head is not flat, you'll need to wrap the ListArray output in a RegularArray
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int64_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
+        return std::shared_ptr<Content>(new ListOffsetArrayOf<T>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
       }
       else {
         Index64 nextcarry(lenstarts);
         Index64 nextadvanced(lenstarts);
-        struct Error err = awkward_listarray64_getitem_next_array_advanced_64(
+        struct Error err = util::awkward_listarray_getitem_next_array_advanced_64<T>(
           nextcarry.ptr().get(),
           nextadvanced.ptr().get(),
           starts_.ptr().get(),
@@ -521,41 +376,15 @@ namespace awkward {
     }
   }
 
-  template <>
-  const std::shared_ptr<Content> ListArrayOf<int32_t>::carry(const Index64& carry) const {
-    int64_t lenstarts = starts_.length();
-    if (stops_.length() < lenstarts) {
-      util::handle_error(failure("len(stops) < len(starts)", kSliceNone, kSliceNone), classname(), id_.get());
-    }
-    Index32 nextstarts(carry.length());
-    Index32 nextstops(carry.length());
-    struct Error err = awkward_listarray32_getitem_carry_64(
-      nextstarts.ptr().get(),
-      nextstops.ptr().get(),
-      starts_.ptr().get(),
-      stops_.ptr().get(),
-      carry.ptr().get(),
-      starts_.offset(),
-      stops_.offset(),
-      lenstarts,
-      carry.length());
-    util::handle_error(err, classname(), id_.get());
-    std::shared_ptr<Identity> id(nullptr);
-    if (id_.get() != nullptr) {
-      id = id_.get()->getitem_carry_64(carry);
-    }
-    return std::shared_ptr<Content>(new ListArrayOf<int32_t>(id, nextstarts, nextstops, content_));
-  }
-
-  template <>
-  const std::shared_ptr<Content> ListArrayOf<int64_t>::carry(const Index64& carry) const {
+  template <typename T>
+  const std::shared_ptr<Content> ListArrayOf<T>::carry(const Index64& carry) const {
     int64_t lenstarts = starts_.length();
     if (stops_.length() < lenstarts) {
       util::handle_error(failure("len(stops) < len(starts)", kSliceNone, kSliceNone), classname(), id_.get());
     }
-    Index64 nextstarts(carry.length());
-    Index64 nextstops(carry.length());
-    struct Error err = awkward_listarray64_getitem_carry_64(
+    IndexOf<T> nextstarts(carry.length());
+    IndexOf<T> nextstops(carry.length());
+    struct Error err = util::awkward_listarray_getitem_carry_64<T>(
       nextstarts.ptr().get(),
       nextstops.ptr().get(),
       starts_.ptr().get(),
@@ -570,7 +399,7 @@ namespace awkward {
     if (id_.get() != nullptr) {
       id = id_.get()->getitem_carry_64(carry);
     }
-    return std::shared_ptr<Content>(new ListArrayOf<int64_t>(id, nextstarts, nextstops, content_));
+    return std::shared_ptr<Content>(new ListArrayOf<T>(id, nextstarts, nextstops, content_));
   }
 
   template <typename T>
@@ -580,5 +409,6 @@ namespace awkward {
   }
 
   template class ListArrayOf<int32_t>;
+  template class ListArrayOf<uint32_t>;
   template class ListArrayOf<int64_t>;
 }
diff --git a/src/libawkward/array/ListOffsetArray.cpp b/src/libawkward/array/ListOffsetArray.cpp
index a1d818ba3b..0257864065 100644
--- a/src/libawkward/array/ListOffsetArray.cpp
+++ b/src/libawkward/array/ListOffsetArray.cpp
@@ -16,6 +16,9 @@ namespace awkward {
     if (std::is_same<T, int32_t>::value) {
       return "ListOffsetArray32";
     }
+    else if (std::is_same<T, uint32_t>::value) {
+      return "ListOffsetArrayU32";
+    }
     else if (std::is_same<T, int64_t>::value) {
       return "ListOffsetArray64";
     }
@@ -90,8 +93,8 @@ namespace awkward {
     id_ = id;
   }
 
-  template <>
-  void ListOffsetArrayOf<int64_t>::setid(const std::shared_ptr<Identity> id) {
+  template <typename T>
+  void ListOffsetArrayOf<T>::setid(const std::shared_ptr<Identity> id) {
     if (id.get() == nullptr) {
       content_.get()->setid(id);
     }
@@ -99,13 +102,13 @@ namespace awkward {
       if (length() != id.get()->length()) {
         util::handle_error(failure("content and its id must have the same length", kSliceNone, kSliceNone), classname(), id_.get());
       }
-      Index64 starts = make_starts(offsets_);
-      Index64 stops = make_stops(offsets_);
+      IndexOf<T> starts = make_starts(offsets_);
+      IndexOf<T> stops = make_stops(offsets_);
       std::shared_ptr<Identity> bigid = id.get()->to64();
       if (Identity64* rawid = dynamic_cast<Identity64*>(bigid.get())) {
         Identity64* rawsubid = new Identity64(Identity::newref(), rawid->fieldloc(), rawid->width() + 1, content_.get()->length());
         std::shared_ptr<Identity> subid(rawsubid);
-        struct Error err = awkward_identity64_from_listarray64(
+        struct Error err = util::awkward_identity64_from_listarray<T>(
           rawsubid->ptr().get(),
           rawid->ptr().get(),
           starts.ptr().get(),
@@ -229,160 +232,8 @@ namespace awkward {
     return std::shared_ptr<Content>(new ListOffsetArrayOf<T>(id, offsets_.getitem_range_unsafe(start, stop + 1), content_));
   }
 
-  template <>
-  const std::shared_ptr<Content> ListOffsetArrayOf<int32_t>::getitem_next(const std::shared_ptr<SliceItem> head, const Slice& tail, const Index64& advanced) const {
-    int64_t lenstarts = offsets_.length() - 1;
-
-    if (head.get() == nullptr) {
-      return shallow_copy();
-    }
-
-    else if (SliceAt* at = dynamic_cast<SliceAt*>(head.get())) {
-      assert(advanced.length() == 0);
-      Index32 starts = make_starts(offsets_);
-      Index32 stops = make_stops(offsets_);
-      std::shared_ptr<SliceItem> nexthead = tail.head();
-      Slice nexttail = tail.tail();
-      Index64 nextcarry(lenstarts);
-      struct Error err = awkward_listarray32_getitem_next_at_64(
-        nextcarry.ptr().get(),
-        starts.ptr().get(),
-        stops.ptr().get(),
-        lenstarts,
-        starts.offset(),
-        stops.offset(),
-        at->at());
-      util::handle_error(err, classname(), id_.get());
-      std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
-      return nextcontent.get()->getitem_next(nexthead, nexttail, advanced);
-    }
-
-    else if (SliceRange* range = dynamic_cast<SliceRange*>(head.get())) {
-      Index32 starts = make_starts(offsets_);
-      Index32 stops = make_stops(offsets_);
-      std::shared_ptr<SliceItem> nexthead = tail.head();
-      Slice nexttail = tail.tail();
-      int64_t start = range->start();
-      int64_t stop = range->stop();
-      int64_t step = range->step();
-      if (step == Slice::none()) {
-        step = 1;
-      }
-      int64_t carrylength;
-      struct Error err1 = awkward_listarray32_getitem_next_range_carrylength(
-        &carrylength,
-        starts.ptr().get(),
-        stops.ptr().get(),
-        lenstarts,
-        starts.offset(),
-        stops.offset(),
-        start,
-        stop,
-        step);
-      util::handle_error(err1, classname(), id_.get());
-
-      Index32 nextoffsets(lenstarts + 1);
-      Index64 nextcarry(carrylength);
-
-      struct Error err2 = awkward_listarray32_getitem_next_range_64(
-        nextoffsets.ptr().get(),
-        nextcarry.ptr().get(),
-        starts.ptr().get(),
-        stops.ptr().get(),
-        lenstarts,
-        starts.offset(),
-        stops.offset(),
-        start,
-        stop,
-        step);
-      util::handle_error(err2, classname(), id_.get());
-      std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
-
-      if (advanced.length() == 0) {
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int32_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, advanced)));
-      }
-      else {
-        int64_t total;
-        struct Error err1 = awkward_listarray32_getitem_next_range_counts_64(
-          &total,
-          nextoffsets.ptr().get(),
-          lenstarts);
-        util::handle_error(err1, classname(), id_.get());
-        Index64 nextadvanced(total);
-        struct Error err2 = awkward_listarray32_getitem_next_range_spreadadvanced_64(
-          nextadvanced.ptr().get(),
-          advanced.ptr().get(),
-          nextoffsets.ptr().get(),
-          lenstarts);
-        util::handle_error(err2, classname(), id_.get());
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int32_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
-      }
-    }
-
-    else if (SliceEllipsis* ellipsis = dynamic_cast<SliceEllipsis*>(head.get())) {
-      return getitem_ellipsis(tail, advanced);
-    }
-
-    else if (SliceNewAxis* newaxis = dynamic_cast<SliceNewAxis*>(head.get())) {
-      return getitem_newaxis(tail, advanced);
-    }
-
-    else if (SliceArray64* array = dynamic_cast<SliceArray64*>(head.get())) {
-      Index32 starts = make_starts(offsets_);
-      Index32 stops = make_stops(offsets_);
-      std::shared_ptr<SliceItem> nexthead = tail.head();
-      Slice nexttail = tail.tail();
-      Index64 flathead = array->ravel();
-      if (advanced.length() == 0) {
-        Index64 nextcarry(lenstarts*flathead.length());
-        Index64 nextadvanced(lenstarts*flathead.length());
-        Index32 nextoffsets(lenstarts + 1);
-        Index32 nextstops(lenstarts);
-        struct Error err = awkward_listarray32_getitem_next_array_64(
-          nextoffsets.ptr().get(),
-          nextcarry.ptr().get(),
-          nextadvanced.ptr().get(),
-          starts.ptr().get(),
-          stops.ptr().get(),
-          flathead.ptr().get(),
-          starts.offset(),
-          stops.offset(),
-          lenstarts,
-          flathead.length(),
-          content_.get()->length());
-        util::handle_error(err, classname(), id_.get());
-        std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
-        // FIXME: if the head is not flat, you'll need to wrap the ListArray output in a RegularArray
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int32_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
-      }
-      else {
-        Index64 nextcarry(lenstarts);
-        Index64 nextadvanced(lenstarts);
-        struct Error err = awkward_listarray32_getitem_next_array_advanced_64(
-          nextcarry.ptr().get(),
-          nextadvanced.ptr().get(),
-          starts.ptr().get(),
-          stops.ptr().get(),
-          flathead.ptr().get(),
-          advanced.ptr().get(),
-          starts.offset(),
-          stops.offset(),
-          lenstarts,
-          flathead.length(),
-          content_.get()->length());
-        util::handle_error(err, classname(), id_.get());
-        std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
-        return nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced);
-      }
-    }
-
-    else {
-      throw std::runtime_error("unrecognized slice item type");
-    }
-  }
-
-  template <>
-  const std::shared_ptr<Content> ListOffsetArrayOf<int64_t>::getitem_next(const std::shared_ptr<SliceItem> head, const Slice& tail, const Index64& advanced) const {
+  template <typename T>
+  const std::shared_ptr<Content> ListOffsetArrayOf<T>::getitem_next(const std::shared_ptr<SliceItem> head, const Slice& tail, const Index64& advanced) const {
     int64_t lenstarts = offsets_.length() - 1;
 
     if (head.get() == nullptr) {
@@ -391,12 +242,12 @@ namespace awkward {
 
     else if (SliceAt* at = dynamic_cast<SliceAt*>(head.get())) {
       assert(advanced.length() == 0);
-      Index64 starts = make_starts(offsets_);
-      Index64 stops = make_stops(offsets_);
+      IndexOf<T> starts = make_starts(offsets_);
+      IndexOf<T> stops = make_stops(offsets_);
       std::shared_ptr<SliceItem> nexthead = tail.head();
       Slice nexttail = tail.tail();
       Index64 nextcarry(lenstarts);
-      struct Error err = awkward_listarray64_getitem_next_at_64(
+      struct Error err = util::awkward_listarray_getitem_next_at_64<T>(
         nextcarry.ptr().get(),
         starts.ptr().get(),
         stops.ptr().get(),
@@ -410,8 +261,8 @@ namespace awkward {
     }
 
     else if (SliceRange* range = dynamic_cast<SliceRange*>(head.get())) {
-      Index64 starts = make_starts(offsets_);
-      Index64 stops = make_stops(offsets_);
+      IndexOf<T> starts = make_starts(offsets_);
+      IndexOf<T> stops = make_stops(offsets_);
       std::shared_ptr<SliceItem> nexthead = tail.head();
       Slice nexttail = tail.tail();
       int64_t start = range->start();
@@ -421,7 +272,7 @@ namespace awkward {
         step = 1;
       }
       int64_t carrylength;
-      struct Error err1 = awkward_listarray64_getitem_next_range_carrylength(
+      struct Error err1 = util::awkward_listarray_getitem_next_range_carrylength<T>(
         &carrylength,
         starts.ptr().get(),
         stops.ptr().get(),
@@ -433,10 +284,10 @@ namespace awkward {
         step);
       util::handle_error(err1, classname(), id_.get());
 
-      Index64 nextoffsets(lenstarts + 1);
+      IndexOf<T> nextoffsets(lenstarts + 1);
       Index64 nextcarry(carrylength);
 
-      struct Error err2 = awkward_listarray64_getitem_next_range_64(
+      struct Error err2 = util::awkward_listarray_getitem_next_range_64<T>(
         nextoffsets.ptr().get(),
         nextcarry.ptr().get(),
         starts.ptr().get(),
@@ -451,23 +302,23 @@ namespace awkward {
       std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
 
       if (advanced.length() == 0) {
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int64_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, advanced)));
+        return std::shared_ptr<Content>(new ListOffsetArrayOf<T>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, advanced)));
       }
       else {
         int64_t total;
-        struct Error err1 = awkward_listarray64_getitem_next_range_counts_64(
+        struct Error err1 = util::awkward_listarray_getitem_next_range_counts_64<T>(
           &total,
           nextoffsets.ptr().get(),
           lenstarts);
         util::handle_error(err1, classname(), id_.get());
         Index64 nextadvanced(total);
-        struct Error err2 = awkward_listarray64_getitem_next_range_spreadadvanced_64(
+        struct Error err2 = util::awkward_listarray_getitem_next_range_spreadadvanced_64<T>(
           nextadvanced.ptr().get(),
           advanced.ptr().get(),
           nextoffsets.ptr().get(),
           lenstarts);
         util::handle_error(err2, classname(), id_.get());
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int64_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
+        return std::shared_ptr<Content>(new ListOffsetArrayOf<T>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
       }
     }
 
@@ -480,17 +331,17 @@ namespace awkward {
     }
 
     else if (SliceArray64* array = dynamic_cast<SliceArray64*>(head.get())) {
-      Index64 starts = make_starts(offsets_);
-      Index64 stops = make_stops(offsets_);
+      IndexOf<T> starts = make_starts(offsets_);
+      IndexOf<T> stops = make_stops(offsets_);
       std::shared_ptr<SliceItem> nexthead = tail.head();
       Slice nexttail = tail.tail();
       Index64 flathead = array->ravel();
       if (advanced.length() == 0) {
         Index64 nextcarry(lenstarts*flathead.length());
         Index64 nextadvanced(lenstarts*flathead.length());
-        Index64 nextoffsets(lenstarts + 1);
-        Index64 nextstops(lenstarts);
-        struct Error err = awkward_listarray64_getitem_next_array_64(
+        IndexOf<T> nextoffsets(lenstarts + 1);
+        IndexOf<T> nextstops(lenstarts);
+        struct Error err = util::awkward_listarray_getitem_next_array_64<T>(
           nextoffsets.ptr().get(),
           nextcarry.ptr().get(),
           nextadvanced.ptr().get(),
@@ -505,12 +356,12 @@ namespace awkward {
         util::handle_error(err, classname(), id_.get());
         std::shared_ptr<Content> nextcontent = content_.get()->carry(nextcarry);
         // FIXME: if the head is not flat, you'll need to wrap the ListArray output in a RegularArray
-        return std::shared_ptr<Content>(new ListOffsetArrayOf<int64_t>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
+        return std::shared_ptr<Content>(new ListOffsetArrayOf<T>(id_, nextoffsets, nextcontent.get()->getitem_next(nexthead, nexttail, nextadvanced)));
       }
       else {
         Index64 nextcarry(lenstarts);
         Index64 nextadvanced(lenstarts);
-        struct Error err = awkward_listarray64_getitem_next_array_advanced_64(
+        struct Error err = util::awkward_listarray_getitem_next_array_advanced_64<T>(
           nextcarry.ptr().get(),
           nextadvanced.ptr().get(),
           starts.ptr().get(),
@@ -533,37 +384,13 @@ namespace awkward {
     }
   }
 
-  template <>
-  const std::shared_ptr<Content> ListOffsetArrayOf<int32_t>::carry(const Index64& carry) const {
-    Index32 starts = make_starts(offsets_);
-    Index32 stops = make_stops(offsets_);
-    Index32 nextstarts(carry.length());
-    Index32 nextstops(carry.length());
-    struct Error err = awkward_listarray32_getitem_carry_64(
-      nextstarts.ptr().get(),
-      nextstops.ptr().get(),
-      starts.ptr().get(),
-      stops.ptr().get(),
-      carry.ptr().get(),
-      starts.offset(),
-      stops.offset(),
-      offsets_.length() - 1,
-      carry.length());
-    util::handle_error(err, classname(), id_.get());
-    std::shared_ptr<Identity> id(nullptr);
-    if (id_.get() != nullptr) {
-      id = id_.get()->getitem_carry_64(carry);
-    }
-    return std::shared_ptr<Content>(new ListArrayOf<int32_t>(id, nextstarts, nextstops, content_));
-  }
-
-  template <>
-  const std::shared_ptr<Content> ListOffsetArrayOf<int64_t>::carry(const Index64& carry) const {
-    Index64 starts = make_starts(offsets_);
-    Index64 stops = make_stops(offsets_);
-    Index64 nextstarts(carry.length());
-    Index64 nextstops(carry.length());
-    struct Error err = awkward_listarray64_getitem_carry_64(
+  template <typename T>
+  const std::shared_ptr<Content> ListOffsetArrayOf<T>::carry(const Index64& carry) const {
+    IndexOf<T> starts = make_starts(offsets_);
+    IndexOf<T> stops = make_stops(offsets_);
+    IndexOf<T> nextstarts(carry.length());
+    IndexOf<T> nextstops(carry.length());
+    struct Error err = util::awkward_listarray_getitem_carry_64<T>(
       nextstarts.ptr().get(),
       nextstops.ptr().get(),
       starts.ptr().get(),
@@ -578,7 +405,7 @@ namespace awkward {
     if (id_.get() != nullptr) {
       id = id_.get()->getitem_carry_64(carry);
     }
-    return std::shared_ptr<Content>(new ListArrayOf<int64_t>(id, nextstarts, nextstops, content_));
+    return std::shared_ptr<Content>(new ListArrayOf<T>(id, nextstarts, nextstops, content_));
   }
 
   template <typename T>
@@ -588,5 +415,6 @@ namespace awkward {
   }
 
   template class ListOffsetArrayOf<int32_t>;
+  template class ListOffsetArrayOf<uint32_t>;
   template class ListOffsetArrayOf<int64_t>;
 }
diff --git a/src/libawkward/util.cpp b/src/libawkward/util.cpp
index 3f51fe6c1e..cf4438f557 100644
--- a/src/libawkward/util.cpp
+++ b/src/libawkward/util.cpp
@@ -3,6 +3,9 @@
 #include <cassert>
 #include <sstream>
 
+#include "awkward/cpu-kernels/identity.h"
+#include "awkward/cpu-kernels/getitem.h"
+
 #include "awkward/util.h"
 #include "awkward/Identity.h"
 
@@ -28,5 +31,119 @@ namespace awkward {
         throw std::invalid_argument(out.str());
       }
     }
+
+    template <>
+    Error awkward_identity64_from_listarray<uint32_t>(int64_t* toptr, const int64_t* fromptr, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth) {
+      return awkward_identity64_from_listarrayU32(toptr, fromptr, fromstarts, fromstops, fromptroffset, startsoffset, stopsoffset, tolength, fromlength, fromwidth);
+    }
+    template <>
+    Error awkward_identity64_from_listarray<int64_t>(int64_t* toptr, const int64_t* fromptr, const int64_t* fromstarts, const int64_t* fromstops, int64_t fromptroffset, int64_t startsoffset, int64_t stopsoffset, int64_t tolength, int64_t fromlength, int64_t fromwidth) {
+      return awkward_identity64_from_listarray64(toptr, fromptr, fromstarts, fromstops, fromptroffset, startsoffset, stopsoffset, tolength, fromlength, fromwidth);
+    }
+
+    template <>
+    Error awkward_listarray_getitem_next_at_64<int32_t>(int64_t* tocarry, const int32_t* fromstarts, const int32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at) {
+      return awkward_listarray32_getitem_next_at_64(tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, at);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_at_64<uint32_t>(int64_t* tocarry, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at) {
+      return awkward_listarrayU32_getitem_next_at_64(tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, at);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_at_64<int64_t>(int64_t* tocarry, const int64_t* fromstarts, const int64_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t at) {
+      return awkward_listarray64_getitem_next_at_64(tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, at);
+    }
+
+    template <>
+    Error awkward_listarray_getitem_next_range_carrylength<int32_t>(int64_t* carrylength, const int32_t* fromstarts, const int32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
+      return awkward_listarray32_getitem_next_range_carrylength(carrylength, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_range_carrylength<uint32_t>(int64_t* carrylength, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
+      return awkward_listarrayU32_getitem_next_range_carrylength(carrylength, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_range_carrylength<int64_t>(int64_t* carrylength, const int64_t* fromstarts, const int64_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
+      return awkward_listarray64_getitem_next_range_carrylength(carrylength, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
+    }
+
+    template <>
+    Error awkward_listarray_getitem_next_range_64<int32_t>(int32_t* tooffsets, int64_t* tocarry, const int32_t* fromstarts, const int32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
+      return awkward_listarray32_getitem_next_range_64(tooffsets, tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_range_64<uint32_t>(uint32_t* tooffsets, int64_t* tocarry, const uint32_t* fromstarts, const uint32_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
+      return awkward_listarrayU32_getitem_next_range_64(tooffsets, tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_range_64<int64_t>(int64_t* tooffsets, int64_t* tocarry, const int64_t* fromstarts, const int64_t* fromstops, int64_t lenstarts, int64_t startsoffset, int64_t stopsoffset, int64_t start, int64_t stop, int64_t step) {
+      return awkward_listarray64_getitem_next_range_64(tooffsets, tocarry, fromstarts, fromstops, lenstarts, startsoffset, stopsoffset, start, stop, step);
+    }
+
+    template <>
+    Error awkward_listarray_getitem_next_range_counts_64<int32_t>(int64_t* total, const int32_t* fromoffsets, int64_t lenstarts) {
+      return awkward_listarray32_getitem_next_range_counts_64(total, fromoffsets, lenstarts);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_range_counts_64<uint32_t>(int64_t* total, const uint32_t* fromoffsets, int64_t lenstarts) {
+      return awkward_listarrayU32_getitem_next_range_counts_64(total, fromoffsets, lenstarts);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_range_counts_64<int64_t>(int64_t* total, const int64_t* fromoffsets, int64_t lenstarts) {
+      return awkward_listarray64_getitem_next_range_counts_64(total, fromoffsets, lenstarts);
+    }
+
+    template <>
+    Error awkward_listarray_getitem_next_range_spreadadvanced_64<int32_t>(int64_t* toadvanced, const int64_t* fromadvanced, const int32_t* fromoffsets, int64_t lenstarts) {
+      return awkward_listarray32_getitem_next_range_spreadadvanced_64(toadvanced, fromadvanced, fromoffsets, lenstarts);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_range_spreadadvanced_64<uint32_t>(int64_t* toadvanced, const int64_t* fromadvanced, const uint32_t* fromoffsets, int64_t lenstarts) {
+      return awkward_listarrayU32_getitem_next_range_spreadadvanced_64(toadvanced, fromadvanced, fromoffsets, lenstarts);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_range_spreadadvanced_64<int64_t>(int64_t* toadvanced, const int64_t* fromadvanced, const int64_t* fromoffsets, int64_t lenstarts) {
+      return awkward_listarray64_getitem_next_range_spreadadvanced_64(toadvanced, fromadvanced, fromoffsets, lenstarts);
+    }
+
+    template <>
+    Error awkward_listarray_getitem_next_array_64<int32_t>(int32_t* tooffsets, int64_t* tocarry, int64_t* toadvanced, const int32_t* fromstarts, const int32_t* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
+      return awkward_listarray32_getitem_next_array_64(tooffsets, tocarry, toadvanced, fromstarts, fromstops, fromarray, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_array_64<uint32_t>(uint32_t* tooffsets, int64_t* tocarry, int64_t* toadvanced, const uint32_t* fromstarts, const uint32_t* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
+      return awkward_listarrayU32_getitem_next_array_64(tooffsets, tocarry, toadvanced, fromstarts, fromstops, fromarray, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_array_64<int64_t>(int64_t* tooffsets, int64_t* tocarry, int64_t* toadvanced, const int64_t* fromstarts, const int64_t* fromstops, const int64_t* fromarray, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
+      return awkward_listarray64_getitem_next_array_64(tooffsets, tocarry, toadvanced, fromstarts, fromstops, fromarray, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
+    }
+
+    template <>
+    Error awkward_listarray_getitem_next_array_advanced_64<int32_t>(int64_t* tocarry, int64_t* toadvanced, const int32_t* fromstarts, const int32_t* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
+      return awkward_listarray32_getitem_next_array_advanced_64(tocarry, toadvanced, fromstarts, fromstops, fromarray, fromadvanced, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_array_advanced_64<uint32_t>(int64_t* tocarry, int64_t* toadvanced, const uint32_t* fromstarts, const uint32_t* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
+      return awkward_listarrayU32_getitem_next_array_advanced_64(tocarry, toadvanced, fromstarts, fromstops, fromarray, fromadvanced, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
+    }
+    template <>
+    Error awkward_listarray_getitem_next_array_advanced_64<int64_t>(int64_t* tocarry, int64_t* toadvanced, const int64_t* fromstarts, const int64_t* fromstops, const int64_t* fromarray, const int64_t* fromadvanced, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lenarray, int64_t lencontent) {
+      return awkward_listarray64_getitem_next_array_advanced_64(tocarry, toadvanced, fromstarts, fromstops, fromarray, fromadvanced, startsoffset, stopsoffset, lenstarts, lenarray, lencontent);
+    }
+
+    template <>
+    Error awkward_listarray_getitem_carry_64<int32_t>(int32_t* tostarts, int32_t* tostops, const int32_t* fromstarts, const int32_t* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry) {
+      return awkward_listarray32_getitem_carry_64(tostarts, tostops, fromstarts, fromstops, fromcarry, startsoffset, stopsoffset, lenstarts, lencarry);
+    }
+    template <>
+    Error awkward_listarray_getitem_carry_64<uint32_t>(uint32_t* tostarts, uint32_t* tostops, const uint32_t* fromstarts, const uint32_t* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry) {
+      return awkward_listarrayU32_getitem_carry_64(tostarts, tostops, fromstarts, fromstops, fromcarry, startsoffset, stopsoffset, lenstarts, lencarry);
+    }
+    template <>
+    Error awkward_listarray_getitem_carry_64<int64_t>(int64_t* tostarts, int64_t* tostops, const int64_t* fromstarts, const int64_t* fromstops, const int64_t* fromcarry, int64_t startsoffset, int64_t stopsoffset, int64_t lenstarts, int64_t lencarry) {
+      return awkward_listarray64_getitem_carry_64(tostarts, tostops, fromstarts, fromstops, fromcarry, startsoffset, stopsoffset, lenstarts, lencarry);
+    }
+
   }
 }
diff --git a/src/pyawkward.cpp b/src/pyawkward.cpp
index 9bedf1b1d8..23b6c490c8 100644
--- a/src/pyawkward.cpp
+++ b/src/pyawkward.cpp
@@ -80,12 +80,18 @@ py::object box(std::shared_ptr<ak::Content> content) {
   else if (ak::ListArray32* raw = dynamic_cast<ak::ListArray32*>(content.get())) {
     return py::cast(*raw);
   }
+  else if (ak::ListArrayU32* raw = dynamic_cast<ak::ListArrayU32*>(content.get())) {
+    return py::cast(*raw);
+  }
   else if (ak::ListArray64* raw = dynamic_cast<ak::ListArray64*>(content.get())) {
     return py::cast(*raw);
   }
   else if (ak::ListOffsetArray32* raw = dynamic_cast<ak::ListOffsetArray32*>(content.get())) {
     return py::cast(*raw);
   }
+  else if (ak::ListOffsetArrayU32* raw = dynamic_cast<ak::ListOffsetArrayU32*>(content.get())) {
+    return py::cast(*raw);
+  }
   else if (ak::ListOffsetArray64* raw = dynamic_cast<ak::ListOffsetArray64*>(content.get())) {
     return py::cast(*raw);
   }
@@ -146,6 +152,10 @@ std::shared_ptr<ak::Content> unbox_content(py::object obj) {
     return obj.cast<ak::ListArray32*>()->shallow_copy();
   }
   catch (py::cast_error err) { }
+  try {
+    return obj.cast<ak::ListArrayU32*>()->shallow_copy();
+  }
+  catch (py::cast_error err) { }
   try {
     return obj.cast<ak::ListArray64*>()->shallow_copy();
   }
@@ -154,6 +164,10 @@ std::shared_ptr<ak::Content> unbox_content(py::object obj) {
     return obj.cast<ak::ListOffsetArray32*>()->shallow_copy();
   }
   catch (py::cast_error err) { }
+  try {
+    return obj.cast<ak::ListOffsetArrayU32*>()->shallow_copy();
+  }
+  catch (py::cast_error err) { }
   try {
     return obj.cast<ak::ListOffsetArray64*>()->shallow_copy();
   }
@@ -777,9 +791,11 @@ PYBIND11_MODULE(layout, m) {
   m.attr("__version__") = "dev";
 #endif
 
-  make_IndexOf<int8_t>(m,  "Index8");
-  make_IndexOf<int32_t>(m, "Index32");
-  make_IndexOf<int64_t>(m, "Index64");
+  make_IndexOf<int8_t>(m,   "Index8");
+  make_IndexOf<uint8_t>(m,  "IndexU8");
+  make_IndexOf<int32_t>(m,  "Index32");
+  make_IndexOf<uint32_t>(m, "IndexU32");
+  make_IndexOf<int64_t>(m,  "Index64");
 
   make_IdentityOf<int32_t>(m, "Identity32");
   make_IdentityOf<int64_t>(m, "Identity64");
@@ -802,11 +818,13 @@ PYBIND11_MODULE(layout, m) {
 
   make_NumpyArray(m, "NumpyArray");
 
-  make_ListArrayOf<int32_t>(m, "ListArray32");
-  make_ListArrayOf<int64_t>(m, "ListArray64");
+  make_ListArrayOf<int32_t>(m,  "ListArray32");
+  make_ListArrayOf<uint32_t>(m, "ListArrayU32");
+  make_ListArrayOf<int64_t>(m,  "ListArray64");
 
-  make_ListOffsetArrayOf<int32_t>(m, "ListOffsetArray32");
-  make_ListOffsetArrayOf<int64_t>(m, "ListOffsetArray64");
+  make_ListOffsetArrayOf<int32_t>(m,  "ListOffsetArray32");
+  make_ListOffsetArrayOf<uint32_t>(m, "ListOffsetArrayU32");
+  make_ListOffsetArrayOf<int64_t>(m,  "ListOffsetArray64");
 
   m.def("fromjson", [](std::string source, int64_t initial, double resize, int64_t buffersize) -> py::object {
     bool isarray = false;
diff --git a/tests/test_PR020_support_unsigned_indexes.py b/tests/test_PR020_support_unsigned_indexes.py
new file mode 100644
index 0000000000..d2a5c317c4
--- /dev/null
+++ b/tests/test_PR020_support_unsigned_indexes.py
@@ -0,0 +1,327 @@
+# BSD 3-Clause License; see https://github.com/jpivarski/awkward-1.0/blob/master/LICENSE
+
+import sys
+import os
+import json
+
+import pytest
+import numpy
+numba = pytest.importorskip("numba")
+
+import awkward1
+
+py27 = (sys.version_info[0] < 3)
+
+def test_index():
+    array_i1 = numpy.array([numpy.iinfo("i1").min, -1, 0, 1, numpy.iinfo("i1").max], dtype="i1")
+    array_u1 = numpy.array([numpy.iinfo("u1").min, -1, 0, 1, numpy.iinfo("u1").max], dtype="u1")
+    array_li2 = numpy.array([numpy.iinfo("<i2").min, -1, 0, 1, numpy.iinfo("<i2").max], dtype="<i2")
+    array_lu2 = numpy.array([numpy.iinfo("<u2").min, -1, 0, 1, numpy.iinfo("<u2").max], dtype="<u2")
+    array_li4 = numpy.array([numpy.iinfo("<i4").min, -1, 0, 1, numpy.iinfo("<i4").max], dtype="<i4")
+    array_lu4 = numpy.array([numpy.iinfo("<u4").min, -1, 0, 1, numpy.iinfo("<u4").max], dtype="<u4")
+    array_li8 = numpy.array([numpy.iinfo("<i8").min, -1, 0, 1, numpy.iinfo("<i8").max], dtype="<i8")
+    array_lu8 = numpy.array([numpy.iinfo("<u8").min, -1, 0, 1, numpy.iinfo("<u8").max], dtype="<u8")
+    array_bi2 = numpy.array([numpy.iinfo(">i2").min, -1, 0, 1, numpy.iinfo(">i2").max], dtype=">i2")
+    array_bu2 = numpy.array([numpy.iinfo(">u2").min, -1, 0, 1, numpy.iinfo(">u2").max], dtype=">u2")
+    array_bi4 = numpy.array([numpy.iinfo(">i4").min, -1, 0, 1, numpy.iinfo(">i4").max], dtype=">i4")
+    array_bu4 = numpy.array([numpy.iinfo(">u4").min, -1, 0, 1, numpy.iinfo(">u4").max], dtype=">u4")
+    array_bi8 = numpy.array([numpy.iinfo(">i8").min, -1, 0, 1, numpy.iinfo(">i8").max], dtype=">i8")
+    array_bu8 = numpy.array([numpy.iinfo(">u8").min, -1, 0, 1, numpy.iinfo(">u8").max], dtype=">u8")
+
+    index_i1 = awkward1.layout.Index8(array_i1)
+    index_u1 = awkward1.layout.IndexU8(array_u1)
+    index_li2 = awkward1.layout.Index32(array_li2)
+    index_lu2 = awkward1.layout.Index32(array_lu2)
+    index_li4 = awkward1.layout.Index32(array_li4)
+    index_lu4 = awkward1.layout.IndexU32(array_lu4)
+    index_li8 = awkward1.layout.Index64(array_li8)
+    index_lu8 = awkward1.layout.Index64(array_lu8)
+    index_bi2 = awkward1.layout.Index32(array_bi2)
+    index_bu2 = awkward1.layout.Index32(array_bu2)
+    index_bi4 = awkward1.layout.Index32(array_bi4)
+    index_bu4 = awkward1.layout.IndexU32(array_bu4)
+    index_bi8 = awkward1.layout.Index64(array_bi8)
+    index_bu8 = awkward1.layout.Index64(array_bu8)
+
+    assert index_i1[2] == 0
+    assert index_u1[2] == 0
+    assert index_li2[2] == 0
+    assert index_lu2[2] == 0
+    assert index_li4[2] == 0
+    assert index_lu4[2] == 0
+    assert index_li8[2] == 0
+    assert index_lu8[2] == 0
+    assert index_bi2[2] == 0
+    assert index_bu2[2] == 0
+    assert index_bi4[2] == 0
+    assert index_bu4[2] == 0
+    assert index_bi8[2] == 0
+    assert index_bu8[2] == 0
+
+    array_i1[2] = 10
+    array_u1[2] = 10
+    array_li2[2] = 10
+    array_lu2[2] = 10
+    array_li4[2] = 10
+    array_lu4[2] = 10
+    array_li8[2] = 10
+    array_lu8[2] = 10
+    array_bi2[2] = 10
+    array_bu2[2] = 10
+    array_bi4[2] = 10
+    array_bu4[2] = 10
+    array_bi8[2] = 10
+    array_bu8[2] = 10
+
+    assert index_i1[2] == 10
+    assert index_u1[2] == 10
+    assert index_li2[2] == 0
+    assert index_lu2[2] == 0
+    assert index_li4[2] == 10
+    assert index_lu4[2] == 10
+    assert index_li8[2] == 10
+    assert index_lu8[2] == 0
+    assert index_bi2[2] == 0
+    assert index_bu2[2] == 0
+    assert index_bi4[2] == 0
+    assert index_bu4[2] == 0
+    assert index_bi8[2] == 0
+    assert index_bu8[2] == 0
+
+content  = awkward1.layout.NumpyArray(numpy.array([1.1, 2.2, 3.3, 4.4, 5.5, 6.6, 7.7, 8.8, 9.9]))
+starts1  = awkward1.layout.IndexU32(numpy.array([0, 3, 3, 5, 6], numpy.uint32))
+stops1   = awkward1.layout.IndexU32(numpy.array([3, 3, 5, 6, 9], numpy.uint32))
+offsets1 = awkward1.layout.IndexU32(numpy.array([0, 3, 3, 5, 6, 9], numpy.uint32))
+starts2  = awkward1.layout.IndexU32(numpy.array([0, 2, 3, 3], numpy.uint32))
+stops2   = awkward1.layout.IndexU32(numpy.array([2, 3, 3, 5], numpy.uint32))
+offsets2 = awkward1.layout.IndexU32(numpy.array([0, 2, 3, 3, 5], numpy.uint32))
+
+def test_listarray_basic():
+    array1 = awkward1.layout.ListArrayU32(starts1, stops1, content)
+    array2 = awkward1.layout.ListArrayU32(starts2, stops2, array1)
+    assert awkward1.tolist(array1) == [[1.1, 2.2, 3.3], [], [4.4, 5.5], [6.6], [7.7, 8.8, 9.9]]
+    assert awkward1.tolist(array1[2]) == [4.4, 5.5]
+    assert awkward1.tolist(array1[1:-1]) == [[], [4.4, 5.5], [6.6]]
+    assert awkward1.tolist(array2) == [[[1.1, 2.2, 3.3], []], [[4.4, 5.5]], [], [[6.6], [7.7, 8.8, 9.9]]]
+    assert awkward1.tolist(array2[1]) == [[4.4, 5.5]]
+    assert awkward1.tolist(array2[1:-1]) == [[[4.4, 5.5]], []]
+
+def test_listoffsetarray_basic():
+    array1 = awkward1.layout.ListOffsetArrayU32(offsets1, content)
+    array2 = awkward1.layout.ListOffsetArrayU32(offsets2, array1)
+    assert awkward1.tolist(array1) == [[1.1, 2.2, 3.3], [], [4.4, 5.5], [6.6], [7.7, 8.8, 9.9]]
+    assert awkward1.tolist(array1[2]) == [4.4, 5.5]
+    assert awkward1.tolist(array1[1:-1]) == [[], [4.4, 5.5], [6.6]]
+    assert awkward1.tolist(array2) == [[[1.1, 2.2, 3.3], []], [[4.4, 5.5]], [], [[6.6], [7.7, 8.8, 9.9]]]
+    assert awkward1.tolist(array2[1]) == [[4.4, 5.5]]
+    assert awkward1.tolist(array2[1:-1]) == [[[4.4, 5.5]], []]
+
+def test_listarray_at():
+    array1 = awkward1.layout.ListArrayU32(starts1, stops1, content)
+    array2 = awkward1.layout.ListArrayU32(starts2, stops2, array1)
+    assert awkward1.tolist(array1[2]) == [4.4, 5.5]
+    assert awkward1.tolist(array1[2,]) == [4.4, 5.5]
+    assert awkward1.tolist(array1[2, 1:]) == [5.5]
+    assert awkward1.tolist(array1[2:, 0]) == [4.4, 6.6, 7.7]
+    assert awkward1.tolist(array1[2:, -1]) == [5.5, 6.6, 9.9]
+
+def test_listoffsetarray_at():
+    array1 = awkward1.layout.ListOffsetArrayU32(offsets1, content)
+    array2 = awkward1.layout.ListOffsetArrayU32(offsets2, array1)
+    assert awkward1.tolist(array1[2,]) == [4.4, 5.5]
+    assert awkward1.tolist(array1[2, 1:]) == [5.5]
+    assert awkward1.tolist(array1[2:, 0]) == [4.4, 6.6, 7.7]
+    assert awkward1.tolist(array1[2:, -1]) == [5.5, 6.6, 9.9]
+
+def test_listarray_slice():
+    array1 = awkward1.layout.ListArrayU32(starts1, stops1, content)
+    array2 = awkward1.layout.ListArrayU32(starts2, stops2, array1)
+    assert awkward1.tolist(array1[1:-1]) == [[], [4.4, 5.5], [6.6]]
+    assert awkward1.tolist(array1[1:-1,]) == [[], [4.4, 5.5], [6.6]]
+    assert awkward1.tolist(array2[1:-1]) == [[[4.4, 5.5]], []]
+    assert awkward1.tolist(array2[1:-1,]) == [[[4.4, 5.5]], []]
+
+def test_listoffsetarray_slice():
+    array1 = awkward1.layout.ListOffsetArrayU32(offsets1, content)
+    array2 = awkward1.layout.ListOffsetArrayU32(offsets2, array1)
+    assert awkward1.tolist(array1[1:-1]) == [[], [4.4, 5.5], [6.6]]
+    assert awkward1.tolist(array1[1:-1,]) == [[], [4.4, 5.5], [6.6]]
+    assert awkward1.tolist(array2[1:-1]) == [[[4.4, 5.5]], []]
+    assert awkward1.tolist(array2[1:-1,]) == [[[4.4, 5.5]], []]
+
+def test_listarray_slice_slice():
+    array1 = awkward1.layout.ListArrayU32(starts1, stops1, content)
+    array2 = awkward1.layout.ListArrayU32(starts2, stops2, array1)
+    assert awkward1.tolist(array1[2:]) == [[4.4, 5.5], [6.6], [7.7, 8.8, 9.9]]
+    assert awkward1.tolist(array1[2:, 1:]) == [[5.5], [], [8.8, 9.9]]
+    assert awkward1.tolist(array1[2:,:-1]) == [[4.4], [], [7.7, 8.8]]
+
+def test_listoffsetarray_slice_slice():
+    array1 = awkward1.layout.ListOffsetArrayU32(offsets1, content)
+    array2 = awkward1.layout.ListOffsetArrayU32(offsets2, array1)
+    assert awkward1.tolist(array1[2:]) == [[4.4, 5.5], [6.6], [7.7, 8.8, 9.9]]
+    assert awkward1.tolist(array1[2:, 1:]) == [[5.5], [], [8.8, 9.9]]
+    assert awkward1.tolist(array1[2:,:-1]) == [[4.4], [], [7.7, 8.8]]
+
+def test_listarray_ellipsis():
+    array1 = awkward1.layout.ListArrayU32(starts1, stops1, content)
+    array2 = awkward1.layout.ListArrayU32(starts2, stops2, array1)
+    if not py27:
+        assert awkward1.tolist(array1[Ellipsis, 1:]) == [[2.2, 3.3], [], [5.5], [], [8.8, 9.9]]
+        assert awkward1.tolist(array2[Ellipsis, 1:]) == [[[2.2, 3.3], []], [[5.5]], [], [[], [8.8, 9.9]]]
+
+def test_listoffsetarray_ellipsis():
+    array1 = awkward1.layout.ListOffsetArrayU32(offsets1, content)
+    array2 = awkward1.layout.ListOffsetArrayU32(offsets2, array1)
+    if not py27:
+        assert awkward1.tolist(array1[Ellipsis, 1:]) == [[2.2, 3.3], [], [5.5], [], [8.8, 9.9]]
+        assert awkward1.tolist(array2[Ellipsis, 1:]) == [[[2.2, 3.3], []], [[5.5]], [], [[], [8.8, 9.9]]]
+
+def test_listarray_array_slice():
+    array1 = awkward1.layout.ListArrayU32(starts1, stops1, content)
+    array2 = awkward1.layout.ListArrayU32(starts2, stops2, array1)
+    assert awkward1.tolist(array2[[0, 0, 1, 1, 1, 0]]) == [[[1.1, 2.2, 3.3], []], [[1.1, 2.2, 3.3], []], [[4.4, 5.5]], [[4.4, 5.5]], [[4.4, 5.5]], [[1.1, 2.2, 3.3], []]]
+    assert awkward1.tolist(array2[[0, 0, 1, 1, 1, 0], :]) == [[[1.1, 2.2, 3.3], []], [[1.1, 2.2, 3.3], []], [[4.4, 5.5]], [[4.4, 5.5]], [[4.4, 5.5]], [[1.1, 2.2, 3.3], []]]
+    assert awkward1.tolist(array2[[0, 0, 1, 1, 1, 0], :, 1:]) == [[[2.2, 3.3], []], [[2.2, 3.3], []], [[5.5]], [[5.5]], [[5.5]], [[2.2, 3.3], []]]
+
+def test_listoffsetarray_array_slice():
+    array1 = awkward1.layout.ListOffsetArrayU32(offsets1, content)
+    array2 = awkward1.layout.ListOffsetArrayU32(offsets2, array1)
+    assert awkward1.tolist(array2[[0, 0, 1, 1, 1, 0]]) == [[[1.1, 2.2, 3.3], []], [[1.1, 2.2, 3.3], []], [[4.4, 5.5]], [[4.4, 5.5]], [[4.4, 5.5]], [[1.1, 2.2, 3.3], []]]
+    assert awkward1.tolist(array2[[0, 0, 1, 1, 1, 0], :]) == [[[1.1, 2.2, 3.3], []], [[1.1, 2.2, 3.3], []], [[4.4, 5.5]], [[4.4, 5.5]], [[4.4, 5.5]], [[1.1, 2.2, 3.3], []]]
+    assert awkward1.tolist(array2[[0, 0, 1, 1, 1, 0], :, 1:]) == [[[2.2, 3.3], []], [[2.2, 3.3], []], [[5.5]], [[5.5]], [[5.5]], [[2.2, 3.3], []]]
+
+def test_listarray_array():
+    array1 = awkward1.layout.ListArrayU32(starts1, stops1, content)
+    array2 = awkward1.layout.ListArrayU32(starts2, stops2, array1)
+    assert awkward1.tolist(array1[numpy.array([2, 0, 0, 1, -1])]) == [[4.4, 5.5], [1.1, 2.2, 3.3], [1.1, 2.2, 3.3], [], [7.7, 8.8, 9.9]]
+    assert awkward1.tolist(array1[numpy.array([2, 0, 0, -1]), numpy.array([1, 1, 0, 0])]) == [5.5, 2.2, 1.1, 7.7]
+
+    content_deep = awkward1.layout.NumpyArray(numpy.array([[0, 0], [1, 10], [2, 20], [3, 30], [4, 40], [5, 50], [6, 60], [7, 70], [8, 80]]))
+    starts1_deep = awkward1.layout.IndexU32(numpy.array([0, 3, 6]))
+    stops1_deep = awkward1.layout.IndexU32(numpy.array([3, 6, 9]))
+    array1_deep = awkward1.layout.ListArrayU32(starts1_deep, stops1_deep, content_deep)
+
+    assert awkward1.tolist(array1_deep) == [[[0, 0], [1, 10], [2, 20]], [[3, 30], [4, 40], [5, 50]], [[6, 60], [7, 70], [8, 80]]]
+    s = (numpy.array([2, 0, 0, -1]), numpy.array([1, 1, 0, 0]), numpy.array([0, 1, 0, 1]))
+    assert numpy.array([[[0, 0], [1, 10], [2, 20]], [[3, 30], [4, 40], [5, 50]], [[6, 60], [7, 70], [8, 80]]])[s].tolist() == awkward1.tolist(array1_deep[s])
+
+    s = (numpy.array([2, 0, 0, -1]), numpy.array([1, 1, 0, 0]), slice(1, None))
+    assert numpy.array([[[0, 0], [1, 10], [2, 20]], [[3, 30], [4, 40], [5, 50]], [[6, 60], [7, 70], [8, 80]]])[s].tolist() == awkward1.tolist(array1_deep[s])
+
+def test_listoffsetarray_array():
+    array1 = awkward1.layout.ListOffsetArrayU32(offsets1, content)
+    array2 = awkward1.layout.ListOffsetArrayU32(offsets2, array1)
+    assert awkward1.tolist(array1[numpy.array([2, 0, 0, 1, -1])]) == [[4.4, 5.5], [1.1, 2.2, 3.3], [1.1, 2.2, 3.3], [], [7.7, 8.8, 9.9]]
+    assert awkward1.tolist(array1[numpy.array([2, 0, 0, -1]), numpy.array([1, 1, 0, 0])]) == [5.5, 2.2, 1.1, 7.7]
+
+    content_deep = awkward1.layout.NumpyArray(numpy.array([[0, 0], [1, 10], [2, 20], [3, 30], [4, 40], [5, 50], [6, 60], [7, 70], [8, 80]]))
+    starts1_deep = awkward1.layout.IndexU32(numpy.array([0, 3, 6]))
+    stops1_deep = awkward1.layout.IndexU32(numpy.array([3, 6, 9]))
+    array1_deep = awkward1.layout.ListArrayU32(starts1_deep, stops1_deep, content_deep)
+
+    assert awkward1.tolist(array1_deep) == [[[0, 0], [1, 10], [2, 20]], [[3, 30], [4, 40], [5, 50]], [[6, 60], [7, 70], [8, 80]]]
+    s = (numpy.array([2, 0, 0, -1]), numpy.array([1, 1, 0, 0]), numpy.array([0, 1, 0, 1]))
+    assert numpy.array([[[0, 0], [1, 10], [2, 20]], [[3, 30], [4, 40], [5, 50]], [[6, 60], [7, 70], [8, 80]]])[s].tolist() == awkward1.tolist(array1_deep[s])
+
+    s = (numpy.array([2, 0, 0, -1]), numpy.array([1, 1, 0, 0]), slice(1, None))
+    assert numpy.array([[[0, 0], [1, 10], [2, 20]], [[3, 30], [4, 40], [5, 50]], [[6, 60], [7, 70], [8, 80]]])[s].tolist() == awkward1.tolist(array1_deep[s])
+
+def test_getitem_array_U32():
+    content = awkward1.layout.NumpyArray(numpy.array([0.0, 1.1, 2.2, 3.3, 4.4, 5.5, 6.6, 7.7, 8.8, 9.9]))
+    listarray = awkward1.layout.ListArrayU32(awkward1.layout.IndexU32(numpy.array([0, 3, 3, 5, 6], numpy.uint32)), awkward1.layout.IndexU32(numpy.array([3, 3, 5, 6, 10], numpy.uint32)), content)
+
+    @numba.njit
+    def f1(q):
+        return q[[2, 0, 0, 1]]
+
+    assert awkward1.tolist(f1(listarray)) == [[3.3, 4.4], [0.0, 1.1, 2.2], [0.0, 1.1, 2.2], []]
+
+    @numba.njit
+    def f2(q):
+        return q[[2, 0, 0, -1], 1]
+
+    assert awkward1.tolist(f2(listarray)) == [4.4, 1.1, 1.1, 7.7]
+
+    @numba.njit
+    def f3(q):
+        return q[[2, 0, 0, -1], [-1, -1, 0, 0]]
+
+    assert awkward1.tolist(f3(listarray)) == [4.4, 2.2, 0.0, 6.6]
+
+    listarray.setid()
+    assert numpy.asarray(f1(listarray).id).tolist() == [[2], [0], [0], [1]]
+    assert numpy.asarray(f2(listarray).id).tolist() == [[2, 1], [0, 1], [0, 1], [4, 1]]
+    assert numpy.asarray(f3(listarray).id).tolist() == [[2, 1], [0, 2], [0, 0], [4, 0]]
+
+def test_deep_listarrayU32():
+    content = awkward1.layout.NumpyArray(numpy.arange(2*3*5*7).reshape(-1, 7))
+    offsetsA = numpy.arange(0, 2*3*5 + 5, 5)
+    offsetsB = numpy.arange(0, 2*3 + 3, 3)
+    startsA, stopsA = offsetsA[:-1], offsetsA[1:]
+    startsB, stopsB = offsetsB[:-1], offsetsB[1:]
+
+    listarrayAU32 = awkward1.layout.ListArrayU32(awkward1.layout.IndexU32(startsA), awkward1.layout.IndexU32(stopsA), content)
+    modelA = numpy.arange(2*3*5*7).reshape(2*3, 5, 7)
+
+    listarrayBU32 = awkward1.layout.ListArrayU32(awkward1.layout.IndexU32(startsB), awkward1.layout.IndexU32(stopsB), listarrayAU32)
+    modelB = numpy.arange(2*3*5*7).reshape(2, 3, 5, 7)
+
+    @numba.njit
+    def f1(q):
+        return q[1, 2, 4]
+
+    assert awkward1.tolist(f1(listarrayBU32)) == awkward1.tolist(f1(modelB))
+
+    @numba.njit
+    def f2(q):
+        return q[1, -1, 4, -2]
+
+    assert f2(listarrayBU32) == f2(modelB)
+
+    @numba.njit
+    def f3(q):
+        return q[1:, ::2, 1:-1, 5::-1]
+
+    assert awkward1.tolist(f3(listarrayBU32)) == awkward1.tolist(f3(modelB))
+
+    @numba.njit
+    def f4(q):
+        return q[numpy.array([0, 1, 1, 0]), ::2, 1:-1, 5::-1]
+
+    assert awkward1.tolist(f4(listarrayBU32)) == awkward1.tolist(f4(modelB))
+
+def test_deep_listoffsetarrayU32():
+    content = awkward1.layout.NumpyArray(numpy.arange(2*3*5*7).reshape(-1, 7))
+    offsetsA = numpy.arange(0, 2*3*5 + 5, 5)
+    offsetsB = numpy.arange(0, 2*3 + 3, 3)
+
+    listoffsetarrayAU32 = awkward1.layout.ListOffsetArrayU32(awkward1.layout.IndexU32(offsetsA), content)
+    modelA = numpy.arange(2*3*5*7).reshape(2*3, 5, 7)
+
+    listoffsetarrayBU32 = awkward1.layout.ListOffsetArrayU32(awkward1.layout.IndexU32(offsetsB), listoffsetarrayAU32)
+    modelB = numpy.arange(2*3*5*7).reshape(2, 3, 5, 7)
+
+    @numba.njit
+    def f1(q):
+        return q[1, 2, 4]
+
+    assert awkward1.tolist(f1(listoffsetarrayBU32)) == awkward1.tolist(f1(modelB))
+
+    @numba.njit
+    def f2(q):
+        return q[1, -1, 4, -2]
+
+    assert f2(listoffsetarrayBU32) == f2(modelB)
+
+    @numba.njit
+    def f3(q):
+        return q[1:, ::2, 1:-1, 5::-1]
+
+    assert awkward1.tolist(f3(listoffsetarrayBU32)) == awkward1.tolist(f3(modelB))
+
+    @numba.njit
+    def f4(q):
+        return q[numpy.array([0, 1, 1, 0]), ::2, 1:-1, 5::-1]
+
+    assert awkward1.tolist(f4(listoffsetarrayBU32)) == awkward1.tolist(f4(modelB))