diff --git a/lib/core30.rng b/lib/core30.rng
index bb9cbd5..2a4409e 100644
--- a/lib/core30.rng
+++ b/lib/core30.rng
@@ -1335,9 +1335,7 @@
       <ref name="global.attributes"/>
       <ref name="step.attributes"/>
       <interleave>
-        <optional>
-          <ref name="WithInput"/>
-        </optional>
+        <ref name="WithInput"/>
         <zeroOrMore>
           <ref name="RunInput"/>
         </zeroOrMore>
diff --git a/lib/core31.rng b/lib/core31.rng
new file mode 100644
index 0000000..2a4409e
--- /dev/null
+++ b/lib/core31.rng
@@ -0,0 +1,1916 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<grammar xmlns:p="http://www.w3.org/ns/xproc" ns="http://www.w3.org/ns/xproc" xmlns:c="http://www.w3.org/ns/xproc-step" xmlns:s="http://www.ascc.net/xml/schematron" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:sa="http://xproc.org/ns/syntax-annotations" xmlns="http://relaxng.org/ns/structure/1.0" datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
+  <!-- This schema neither supports nor requires the use of RELAX NG DTD Compatibility -->
+  <define name="XPathExpression" sa:model="XPathExpression">
+    <text/>
+  </define>
+  <define name="XSLTSelectionPattern" sa:model="XSLTSelectionPattern">
+    <text/>
+  </define>
+  <define name="XPathSequenceType" sa:model="XPathSequenceType">
+    <text/>
+  </define>
+  <define name="ContentType" sa:model="ContentType">
+    <text/>
+  </define>
+  <define name="ContentTypes" sa:model="ContentTypes">
+    <text/>
+  </define>
+  <define name="PropertyMap" sa:model="map(xs:QName,item()*)">
+    <text/>
+  </define>
+  <define name="SerializationMap" sa:model="map(xs:QName,item()*)">
+    <text/>
+  </define>
+  <define name="ListOfEQName" sa:model="EQName*">
+    <text/>
+  </define>
+  <define name="Char" sa:model="char">
+    <text/>
+  </define>
+  <!--
+    Copied from the grammar for xslt30.
+    It is possible to construct attribute values that are valid
+    but fail to pass this regexp. But this catches most of them.
+  -->
+  <define name="avt.datatype">
+    <data type="string">
+      <param name="pattern">([^\{\}]|\{\{|\}\}|\{([^"'\{\}]|"[^"]*"|'[^']*')+\})*</param>
+    </data>
+  </define>
+  <define name="name.ncname.attr">
+    <attribute name="name">
+      <data type="NCName"/>
+    </attribute>
+  </define>
+  <define name="name.qname.attr">
+    <attribute name="name">
+      <data type="QName"/>
+    </attribute>
+  </define>
+  <define name="as.attr">
+    <attribute name="as">
+      <ref name="XPathSequenceType"/>
+    </attribute>
+  </define>
+  <define name="port.attr">
+    <attribute name="port">
+      <data type="NCName"/>
+    </attribute>
+  </define>
+  <define name="required.attr">
+    <attribute name="required">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="sequence.attr">
+    <attribute name="sequence">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="primary.attr">
+    <attribute name="primary">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="select.attr">
+    <attribute name="select">
+      <ref name="XPathExpression"/>
+    </attribute>
+  </define>
+  <define name="xpath-version.attr">
+    <attribute name="xpath-version">
+      <data type="decimal"/>
+    </attribute>
+  </define>
+  <define name="psvi-required.attr">
+    <attribute name="psvi-required">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="document-properties.attr">
+    <attribute name="document-properties">
+      <ref name="PropertyMap"/>
+    </attribute>
+  </define>
+  <define name="serialization.attr">
+    <attribute name="serialization">
+      <ref name="SerializationMap"/>
+    </attribute>
+  </define>
+  <define name="content-type.attr">
+    <attribute name="content-type">
+      <ref name="ContentType"/>
+    </attribute>
+  </define>
+  <define name="content-types.attr">
+    <attribute name="content-types">
+      <ref name="ContentTypes"/>
+    </attribute>
+  </define>
+  <define name="collection.attr">
+    <attribute name="collection">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="pipe.attr">
+    <attribute name="pipe"/>
+  </define>
+  <define name="static.attr">
+    <attribute name="static">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="visibility.attr">
+    <attribute name="visibility">
+      <choice>
+        <value>private</value>
+        <value>public</value>
+      </choice>
+    </attribute>
+  </define>
+  <define name="exclude-inline-prefixes.attr">
+    <attribute name="exclude-inline-prefixes">
+      <ref name="ExcludeInlinePrefixes"/>
+    </attribute>
+  </define>
+  <!--
+    Bah, humbug. The ExcludeInlinePrefixes pattern should
+    really be ("#all" | (PrefixList & "#default"?)) or
+    maybe ("#all" | (PrefixList | "#default")+), but neither
+    one of those is allowed by RELAX NG.
+  -->
+  <define name="ExcludeInlinePrefixes" sa:model="ExcludeInlinePrefixes">
+    <text/>
+  </define>
+  <define name="PrefixList" sa:model="PrefixList">
+    <data type="NMTOKENS"/>
+  </define>
+  <define name="EQNameList" sa:model="EQNameList">
+    <data type="NMTOKENS"/>
+  </define>
+  <define name="xmllang.attr" sa:ignore="yes">
+    <attribute name="xml:lang"/>
+  </define>
+  <define name="xmlspace.attr" sa:ignore="yes">
+    <attribute name="xml:space">
+      <choice>
+        <value>default</value>
+        <value>preserve</value>
+      </choice>
+    </attribute>
+  </define>
+  <define name="xmlid.attr" sa:ignore="yes">
+    <attribute name="xml:id">
+      <data type="ID"/>
+    </attribute>
+  </define>
+  <define name="xmlbase.attr" sa:ignore="yes">
+    <attribute name="xml:base">
+      <data type="anyURI"/>
+    </attribute>
+  </define>
+  <define name="href.attr">
+    <attribute name="href">
+      <data type="anyURI"/>
+    </attribute>
+  </define>
+  <define name="use-when.attr" sa:ignore="yes">
+    <attribute name="use-when">
+      <ref name="XPathExpression"/>
+    </attribute>
+  </define>
+  <define name="p_use-when.attr" sa:ignore="yes">
+    <attribute name="p:use-when">
+      <ref name="XPathExpression"/>
+    </attribute>
+  </define>
+  <define name="expand-text.attr" sa:ignore="yes">
+    <attribute name="expand-text">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="p_expand-text.attr" sa:ignore="yes">
+    <attribute name="p:expand-text">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="inline-expand-text.attr" sa:ignore="yes">
+    <attribute name="inline-expand-text">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="p_inline-expand-text.attr" sa:ignore="yes">
+    <attribute name="p:inline-expand-text">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="depends.attr" sa:ignore="yes">
+    <attribute name="depends">
+      <data type="NMTOKENS"/>
+    </attribute>
+  </define>
+  <define name="p_depends.attr" sa:ignore="yes">
+    <attribute name="p:depends">
+      <data type="NMTOKENS"/>
+    </attribute>
+  </define>
+  <define name="timeout.attr" sa:ignore="yes">
+    <attribute name="timeout">
+      <data type="nonNegativeInteger"/>
+    </attribute>
+  </define>
+  <define name="p_timeout.attr" sa:ignore="yes">
+    <attribute name="p:timeout">
+      <data type="nonNegativeInteger"/>
+    </attribute>
+  </define>
+  <define name="message.attr" sa:ignore="yes">
+    <attribute name="message"/>
+  </define>
+  <define name="p_message.attr" sa:ignore="yes">
+    <attribute name="p:message"/>
+  </define>
+  <define name="version.attr">
+    <attribute name="version">
+      <data type="decimal"/>
+    </attribute>
+  </define>
+  <define name="common.attributes">
+    <interleave>
+      <optional>
+        <ref name="xmllang.attr"/>
+      </optional>
+      <optional>
+        <ref name="xmlspace.attr"/>
+      </optional>
+      <optional>
+        <ref name="xmlid.attr"/>
+      </optional>
+      <optional>
+        <ref name="xmlbase.attr"/>
+      </optional>
+      <zeroOrMore>
+        <ref name="extension.attr"/>
+      </zeroOrMore>
+    </interleave>
+  </define>
+  <define name="global.attributes">
+    <optional>
+      <ref name="use-when.attr"/>
+    </optional>
+    <optional>
+      <ref name="expand-text.attr"/>
+    </optional>
+  </define>
+  <define name="p_global.attributes">
+    <optional>
+      <ref name="p_use-when.attr"/>
+    </optional>
+    <optional>
+      <ref name="p_expand-text.attr"/>
+    </optional>
+  </define>
+  <define name="step.attributes">
+    <optional>
+      <ref name="depends.attr"/>
+    </optional>
+    <optional>
+      <ref name="timeout.attr"/>
+    </optional>
+    <optional>
+      <ref name="message.attr"/>
+    </optional>
+  </define>
+  <define name="p_step.attributes">
+    <optional>
+      <ref name="p_depends.attr"/>
+    </optional>
+    <optional>
+      <ref name="p_timeout.attr"/>
+    </optional>
+    <optional>
+      <ref name="p_message.attr"/>
+    </optional>
+  </define>
+  <define name="inline.attributes">
+    <optional>
+      <ref name="exclude-inline-prefixes.attr"/>
+    </optional>
+  </define>
+  <define name="decl.attributes">
+    <optional>
+      <ref name="psvi-required.attr"/>
+    </optional>
+    <optional>
+      <ref name="xpath-version.attr"/>
+    </optional>
+    <optional>
+      <ref name="exclude-inline-prefixes.attr"/>
+    </optional>
+    <optional>
+      <ref name="version.attr"/>
+    </optional>
+  </define>
+  <!-- ============================================================ -->
+  <start>
+    <choice>
+      <ref name="Library"/>
+      <ref name="DeclareStep"/>
+      <ref name="VocabParam"/>
+      <ref name="VocabParamSet"/>
+      <ref name="VocabResult"/>
+      <ref name="VocabHttpRequest"/>
+      <ref name="VocabHeader"/>
+      <ref name="VocabMultipart"/>
+      <ref name="VocabBody"/>
+      <ref name="VocabHttpResponse"/>
+      <ref name="VocabQuery"/>
+      <ref name="VocabLine"/>
+      <ref name="VocabData"/>
+      <ref name="VocabDirectory"/>
+      <ref name="VocabArchive"/>
+      <ref name="Errors"/>
+      <ref name="StandardStep"/>
+      <ref name="ExtraStep"/>
+    </choice>
+  </start>
+  <!-- StandardStep is explicitly unspecified because this is not a complete schema -->
+  <define name="ExtraStep">
+    <notAllowed/>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Library" sa:class="language-construct">
+    <element name="library">
+      <ref name="decl.attributes"/>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="Import"/>
+          <ref name="ImportFunctions"/>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+      <zeroOrMore>
+        <choice>
+          <ref name="StaticOption"/>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+      <zeroOrMore>
+        <choice>
+          <ref name="DeclareStep"/>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="Import" sa:class="language-construct">
+    <element name="import">
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="href.attr"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="ImportFunctions" sa:class="language-construct">
+    <element name="import-functions">
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="href.attr"/>
+      <optional>
+        <ref name="content-type.attr"/>
+      </optional>
+      <optional>
+        <attribute name="namespace"/>
+      </optional>
+      <zeroOrMore>
+        <choice>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="Subpipeline" sa:model="subpipeline">
+    <oneOrMore>
+      <choice>
+        <ref name="Variable"/>
+        <ref name="ForEach"/>
+        <ref name="Viewport"/>
+        <ref name="Choose"/>
+        <ref name="If"/>
+        <ref name="Group"/>
+        <ref name="Try"/>
+        <ref name="OtherStep"/>
+        <ref name="Documentation"/>
+        <ref name="PipeInfo"/>
+      </choice>
+    </oneOrMore>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Input" sa:class="language-construct" sa:element="input">
+    <element name="input">
+      <ref name="port.attr"/>
+      <optional>
+        <ref name="sequence.attr"/>
+      </optional>
+      <optional>
+        <ref name="primary.attr"/>
+      </optional>
+      <optional>
+        <ref name="select.attr"/>
+      </optional>
+      <optional>
+        <ref name="content-types.attr"/>
+      </optional>
+      <optional>
+        <ref name="href.attr" sa:avt="true"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="inline.attributes"/>
+      <choice>
+        <interleave>
+          <choice>
+            <ref name="Empty"/>
+            <zeroOrMore>
+              <choice>
+                <ref name="Document"/>
+                <ref name="Inline"/>
+              </choice>
+            </zeroOrMore>
+          </choice>
+          <zeroOrMore>
+            <choice>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+        <zeroOrMore>
+          <ref name="AnyElement"/>
+        </zeroOrMore>
+      </choice>
+    </element>
+  </define>
+  <define name="WithInput" sa:class="language-construct" sa:element="with-input">
+    <element name="with-input">
+      <optional>
+        <ref name="port.attr"/>
+      </optional>
+      <optional>
+        <ref name="select.attr"/>
+      </optional>
+      <optional>
+        <ref name="href.attr" sa:avt="true"/>
+      </optional>
+      <optional>
+        <ref name="pipe.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="inline.attributes"/>
+      <choice>
+        <interleave>
+          <choice>
+            <ref name="Empty"/>
+            <zeroOrMore>
+              <choice>
+                <ref name="Document"/>
+                <ref name="Pipe"/>
+                <ref name="Inline"/>
+              </choice>
+            </zeroOrMore>
+          </choice>
+          <zeroOrMore>
+            <choice>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+        <zeroOrMore>
+          <ref name="AnyElement"/>
+        </zeroOrMore>
+      </choice>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="AtomicOutputDeclaration" sa:class="language-construct">
+    <element name="output">
+      <optional>
+        <ref name="port.attr"/>
+      </optional>
+      <optional>
+        <ref name="sequence.attr"/>
+      </optional>
+      <optional>
+        <ref name="primary.attr"/>
+      </optional>
+      <optional>
+        <ref name="content-types.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="CompoundOutputDeclaration" sa:class="language-construct">
+    <element name="output">
+      <optional>
+        <ref name="port.attr"/>
+      </optional>
+      <optional>
+        <ref name="sequence.attr"/>
+      </optional>
+      <optional>
+        <ref name="primary.attr"/>
+      </optional>
+      <optional>
+        <ref name="content-types.attr"/>
+      </optional>
+      <optional>
+        <ref name="href.attr" sa:avt="true"/>
+      </optional>
+      <optional>
+        <ref name="pipe.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="inline.attributes"/>
+      <choice>
+        <interleave>
+          <choice>
+            <ref name="Empty"/>
+            <zeroOrMore>
+              <choice>
+                <ref name="Document"/>
+                <ref name="Pipe"/>
+                <ref name="Inline"/>
+              </choice>
+            </zeroOrMore>
+          </choice>
+          <zeroOrMore>
+            <choice>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+        <zeroOrMore>
+          <ref name="AnyElement"/>
+        </zeroOrMore>
+      </choice>
+    </element>
+  </define>
+  <define name="PipelineOutputDeclaration" sa:class="language-construct">
+    <element name="output">
+      <optional>
+        <ref name="port.attr"/>
+      </optional>
+      <optional>
+        <ref name="sequence.attr"/>
+      </optional>
+      <optional>
+        <ref name="primary.attr"/>
+      </optional>
+      <optional>
+        <ref name="content-types.attr"/>
+      </optional>
+      <optional>
+        <ref name="href.attr" sa:avt="true"/>
+      </optional>
+      <optional>
+        <ref name="pipe.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="inline.attributes"/>
+      <optional>
+        <ref name="serialization.attr"/>
+      </optional>
+      <choice>
+        <interleave>
+          <choice>
+            <ref name="Empty"/>
+            <zeroOrMore>
+              <choice>
+                <ref name="Document"/>
+                <ref name="Pipe"/>
+                <ref name="Inline"/>
+              </choice>
+            </zeroOrMore>
+          </choice>
+          <zeroOrMore>
+            <choice>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+        <zeroOrMore>
+          <ref name="AnyElement"/>
+        </zeroOrMore>
+      </choice>
+    </element>
+  </define>
+  <define name="Output" sa:element="output">
+    <choice>
+      <ref name="CompoundOutputDeclaration"/>
+      <ref name="AtomicOutputDeclaration"/>
+      <ref name="PipelineOutputDeclaration"/>
+    </choice>
+  </define>
+  <define name="Pipe" sa:class="language-construct">
+    <element name="pipe">
+      <optional>
+        <attribute name="step">
+          <data type="NCName"/>
+        </attribute>
+      </optional>
+      <optional>
+        <ref name="port.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="Document" sa:class="language-construct">
+    <element name="document">
+      <ref name="href.attr" sa:avt="true"/>
+      <optional>
+        <attribute name="content-type"/>
+      </optional>
+      <optional>
+        <ref name="document-properties.attr"/>
+      </optional>
+      <optional>
+        <attribute name="parameters">
+          <ref name="PropertyMap"/>
+        </attribute>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="Inline" sa:class="language-construct">
+    <element name="inline">
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="inline.attributes"/>
+      <optional>
+        <attribute name="content-type"/>
+      </optional>
+      <optional>
+        <ref name="document-properties.attr"/>
+      </optional>
+      <optional>
+        <attribute name="encoding"/>
+      </optional>
+      <zeroOrMore>
+        <ref name="Any"/>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="Empty" sa:class="language-construct">
+    <element name="empty">
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Option" sa:class="language-construct">
+    <element name="option">
+      <ref name="name.qname.attr"/>
+      <optional>
+        <ref name="as.attr"/>
+      </optional>
+      <optional>
+        <attribute name="values"/>
+      </optional>
+      <optional>
+        <ref name="static.attr"/>
+      </optional>
+      <optional>
+        <ref name="required.attr"/>
+      </optional>
+      <optional>
+        <ref name="select.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <optional>
+        <ref name="visibility.attr"/>
+      </optional>
+      <zeroOrMore>
+        <choice>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="StaticOption" sa:class="language-construct">
+    <element name="option">
+      <ref name="name.qname.attr"/>
+      <optional>
+        <ref name="as.attr"/>
+      </optional>
+      <optional>
+        <attribute name="values"/>
+      </optional>
+      <attribute name="static">
+        <value>true</value>
+      </attribute>
+      <ref name="select.attr"/>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <optional>
+        <ref name="visibility.attr"/>
+      </optional>
+      <zeroOrMore>
+        <choice>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="WithOption" sa:class="language-construct">
+    <element name="with-option">
+      <ref name="name.qname.attr"/>
+      <optional>
+        <ref name="as.attr"/>
+      </optional>
+      <ref name="select.attr"/>
+      <optional>
+        <ref name="collection.attr"/>
+      </optional>
+      <optional>
+        <ref name="href.attr" sa:avt="true"/>
+      </optional>
+      <optional>
+        <ref name="pipe.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="inline.attributes"/>
+      <choice>
+        <interleave>
+          <choice>
+            <ref name="Empty"/>
+            <zeroOrMore>
+              <choice>
+                <ref name="Document"/>
+                <ref name="Pipe"/>
+                <ref name="Inline"/>
+              </choice>
+            </zeroOrMore>
+          </choice>
+          <zeroOrMore>
+            <choice>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+        <zeroOrMore>
+          <ref name="AnyElement"/>
+        </zeroOrMore>
+      </choice>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Variable" sa:class="language-construct">
+    <element name="variable">
+      <ref name="name.qname.attr"/>
+      <optional>
+        <ref name="as.attr"/>
+      </optional>
+      <ref name="select.attr"/>
+      <optional>
+        <ref name="collection.attr"/>
+      </optional>
+      <optional>
+        <ref name="href.attr" sa:avt="true"/>
+      </optional>
+      <optional>
+        <ref name="pipe.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="inline.attributes"/>
+      <choice>
+        <interleave>
+          <choice>
+            <ref name="Empty"/>
+            <zeroOrMore>
+              <choice>
+                <ref name="Document"/>
+                <ref name="Pipe"/>
+                <ref name="Inline"/>
+              </choice>
+            </zeroOrMore>
+          </choice>
+          <zeroOrMore>
+            <choice>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+        <zeroOrMore>
+          <ref name="AnyElement"/>
+        </zeroOrMore>
+      </choice>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="DeclarePipelineStep" sa:class="language-construct">
+    <element name="declare-step">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <optional>
+        <attribute name="type">
+          <data type="QName"/>
+        </attribute>
+      </optional>
+      <ref name="decl.attributes"/>
+      <optional>
+        <ref name="visibility.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="Import"/>
+          <ref name="ImportFunctions"/>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+      <zeroOrMore>
+        <choice>
+          <ref name="Input"/>
+          <ref name="Output"/>
+          <ref name="Option"/>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+      <zeroOrMore>
+        <choice>
+          <ref name="DeclareStep"/>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+      <optional>
+        <ref name="Subpipeline"/>
+      </optional>
+    </element>
+  </define>
+  <define name="DeclareAtomicStep" sa:class="language-construct">
+    <element name="declare-step">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <optional>
+        <attribute name="type">
+          <data type="QName"/>
+        </attribute>
+      </optional>
+      <ref name="decl.attributes"/>
+      <optional>
+        <ref name="visibility.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="Input"/>
+          <ref name="AtomicOutputDeclaration"/>
+          <ref name="Option"/>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="DeclareStep" sa:element="declare-step">
+    <choice>
+      <ref name="DeclarePipelineStep"/>
+      <ref name="DeclareAtomicStep"/>
+    </choice>
+  </define>
+  <!-- ============================================================ -->
+  <define name="ForEach" sa:class="language-construct">
+    <element name="for-each">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="step.attributes"/>
+      <group>
+        <interleave>
+          <optional>
+            <ref name="WithInput"/>
+          </optional>
+          <zeroOrMore>
+            <choice>
+              <ref name="Output"/>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+        <ref name="Subpipeline"/>
+      </group>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Viewport" sa:class="language-construct">
+    <element name="viewport">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <attribute name="match">
+        <ref name="XSLTSelectionPattern"/>
+      </attribute>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="step.attributes"/>
+      <group>
+        <interleave>
+          <optional>
+            <ref name="WithInput"/>
+          </optional>
+          <optional>
+            <ref name="Output"/>
+          </optional>
+          <zeroOrMore>
+            <ref name="Documentation"/>
+          </zeroOrMore>
+          <zeroOrMore>
+            <ref name="PipeInfo"/>
+          </zeroOrMore>
+        </interleave>
+        <ref name="Subpipeline"/>
+      </group>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Choose" sa:class="language-construct">
+    <element name="choose">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="step.attributes"/>
+      <group>
+        <zeroOrMore>
+          <choice>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <optional>
+          <ref name="WithInput"/>
+        </optional>
+        <choice>
+          <group>
+            <oneOrMore>
+              <zeroOrMore>
+                <choice>
+                  <ref name="Documentation"/>
+                  <ref name="PipeInfo"/>
+                </choice>
+              </zeroOrMore>
+              <ref name="When"/>
+            </oneOrMore>
+            <optional>
+              <zeroOrMore>
+                <choice>
+                  <ref name="Documentation"/>
+                  <ref name="PipeInfo"/>
+                </choice>
+              </zeroOrMore>
+              <ref name="Otherwise"/>
+            </optional>
+          </group>
+          <group>
+            <zeroOrMore>
+              <zeroOrMore>
+                <choice>
+                  <ref name="Documentation"/>
+                  <ref name="PipeInfo"/>
+                </choice>
+              </zeroOrMore>
+              <ref name="When"/>
+            </zeroOrMore>
+            <group>
+              <zeroOrMore>
+                <choice>
+                  <ref name="Documentation"/>
+                  <ref name="PipeInfo"/>
+                </choice>
+              </zeroOrMore>
+              <ref name="Otherwise"/>
+            </group>
+          </group>
+        </choice>
+        <zeroOrMore>
+          <choice>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+      </group>
+    </element>
+  </define>
+  <define name="When" sa:class="language-construct">
+    <element name="when">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <attribute name="test">
+        <ref name="XPathExpression"/>
+      </attribute>
+      <optional>
+        <ref name="collection.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <group>
+        <zeroOrMore>
+          <choice>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <optional>
+          <ref name="WithInput"/>
+        </optional>
+        <zeroOrMore>
+          <choice>
+            <ref name="Output"/>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <ref name="Subpipeline"/>
+      </group>
+    </element>
+  </define>
+  <define name="Otherwise" sa:class="language-construct">
+    <element name="otherwise">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <group>
+        <zeroOrMore>
+          <choice>
+            <ref name="Output"/>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <ref name="Subpipeline"/>
+      </group>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="If" sa:class="language-construct">
+    <element name="if">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <attribute name="test">
+        <ref name="XPathExpression"/>
+      </attribute>
+      <optional>
+        <ref name="collection.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="step.attributes"/>
+      <group>
+        <zeroOrMore>
+          <choice>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <optional>
+          <ref name="WithInput"/>
+        </optional>
+        <zeroOrMore>
+          <choice>
+            <ref name="Output"/>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <ref name="Subpipeline"/>
+      </group>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Group" sa:class="language-construct">
+    <element name="group">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="step.attributes"/>
+      <group>
+        <zeroOrMore>
+          <choice>
+            <ref name="Output"/>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <ref name="Subpipeline"/>
+      </group>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Try" sa:class="language-construct">
+    <element name="try">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="step.attributes"/>
+      <group>
+        <zeroOrMore>
+          <choice>
+            <ref name="Output"/>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <ref name="Subpipeline"/>
+        <interleave>
+          <choice>
+            <group>
+              <oneOrMore>
+                <ref name="Catch"/>
+              </oneOrMore>
+              <optional>
+                <ref name="Finally"/>
+              </optional>
+            </group>
+            <group>
+              <zeroOrMore>
+                <ref name="Catch"/>
+              </zeroOrMore>
+              <ref name="Finally"/>
+            </group>
+          </choice>
+          <zeroOrMore>
+            <choice>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+      </group>
+    </element>
+  </define>
+  <define name="Catch" sa:class="language-construct">
+    <element name="catch">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <optional>
+        <attribute name="code">
+          <ref name="EQNameList"/>
+        </attribute>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <group>
+        <zeroOrMore>
+          <choice>
+            <ref name="Output"/>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <ref name="Subpipeline"/>
+      </group>
+    </element>
+  </define>
+  <define name="Finally" sa:class="language-construct">
+    <element name="finally">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <group>
+        <zeroOrMore>
+          <choice>
+            <ref name="Output"/>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <ref name="Subpipeline"/>
+      </group>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="OtherAtomicStep" sa:class="language-construct">
+    <element>
+      <anyName>
+        <except>
+          <nsName/>
+        </except>
+      </anyName>
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <zeroOrMore>
+        <ref name="option.attr"/>
+      </zeroOrMore>
+      <ref name="common.attributes"/>
+      <ref name="p_global.attributes"/>
+      <ref name="p_step.attributes"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="WithInput"/>
+          <ref name="WithOption"/>
+          <ref name="Documentation"/>
+          <ref name="PipeInfo"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="OtherCompoundStep" sa:class="language-construct">
+    <element>
+      <anyName>
+        <except>
+          <nsName/>
+        </except>
+      </anyName>
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="p_global.attributes"/>
+      <ref name="p_step.attributes"/>
+      <group>
+        <zeroOrMore>
+          <choice>
+            <ref name="Output"/>
+            <ref name="Documentation"/>
+            <ref name="PipeInfo"/>
+          </choice>
+        </zeroOrMore>
+        <ref name="Subpipeline"/>
+      </group>
+    </element>
+  </define>
+  <define name="OtherStep">
+    <choice>
+      <ref name="StandardStep"/>
+      <ref name="OtherAtomicStep"/>
+      <ref name="OtherCompoundStep"/>
+    </choice>
+  </define>
+  <!--
+    ============================================================
+    The p:run step is magic.
+  -->
+  <define name="Step-run">
+    <element name="run">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="step.attributes"/>
+      <interleave>
+        <ref name="WithInput"/>
+        <zeroOrMore>
+          <ref name="RunInput"/>
+        </zeroOrMore>
+        <zeroOrMore>
+          <ref name="RunOption"/>
+        </zeroOrMore>
+        <zeroOrMore>
+          <ref name="Output"/>
+        </zeroOrMore>
+        <zeroOrMore>
+          <ref name="Documentation"/>
+        </zeroOrMore>
+        <zeroOrMore>
+          <ref name="PipeInfo"/>
+        </zeroOrMore>
+      </interleave>
+    </element>
+  </define>
+  <define name="RunInput" sa:class="language-construct" sa:element="run-input">
+    <element name="run-input">
+      <ref name="port.attr"/>
+      <optional>
+        <ref name="select.attr"/>
+      </optional>
+      <optional>
+        <ref name="href.attr" sa:avt="true"/>
+      </optional>
+      <optional>
+        <ref name="pipe.attr"/>
+      </optional>
+      <optional>
+        <ref name="primary.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="inline.attributes"/>
+      <choice>
+        <interleave>
+          <choice>
+            <ref name="Empty"/>
+            <zeroOrMore>
+              <choice>
+                <ref name="Document"/>
+                <ref name="Pipe"/>
+                <ref name="Inline"/>
+              </choice>
+            </zeroOrMore>
+          </choice>
+          <zeroOrMore>
+            <choice>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+        <zeroOrMore>
+          <ref name="AnyElement"/>
+        </zeroOrMore>
+      </choice>
+    </element>
+  </define>
+  <define name="RunOption" sa:class="language-construct">
+    <element name="run-option">
+      <ref name="name.qname.attr"/>
+      <optional>
+        <ref name="as.attr"/>
+      </optional>
+      <ref name="select.attr"/>
+      <optional>
+        <ref name="collection.attr"/>
+      </optional>
+      <optional>
+        <ref name="href.attr" sa:avt="true"/>
+      </optional>
+      <optional>
+        <ref name="pipe.attr"/>
+      </optional>
+      <optional>
+        <ref name="static.attr"/>
+      </optional>
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <ref name="inline.attributes"/>
+      <choice>
+        <interleave>
+          <choice>
+            <ref name="Empty"/>
+            <zeroOrMore>
+              <choice>
+                <ref name="Document"/>
+                <ref name="Pipe"/>
+                <ref name="Inline"/>
+              </choice>
+            </zeroOrMore>
+          </choice>
+          <zeroOrMore>
+            <choice>
+              <ref name="Documentation"/>
+              <ref name="PipeInfo"/>
+            </choice>
+          </zeroOrMore>
+        </interleave>
+        <zeroOrMore>
+          <ref name="AnyElement"/>
+        </zeroOrMore>
+      </choice>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Documentation" sa:ignore="yes" sa:class="language-construct">
+    <element name="documentation">
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <zeroOrMore>
+        <ref name="DocContent"/>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="DocContent" sa:model="any-well-formed-content">
+    <ref name="Any"/>
+  </define>
+  <!-- ============================================================ -->
+  <define name="PipeInfo" sa:ignore="yes" sa:class="language-construct">
+    <element name="pipeinfo">
+      <ref name="common.attributes"/>
+      <ref name="global.attributes"/>
+      <zeroOrMore>
+        <ref name="DocContent"/>
+      </zeroOrMore>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="_any.attr">
+    <attribute>
+      <anyName/>
+    </attribute>
+  </define>
+  <define name="option.attr">
+    <attribute>
+      <nsName ns="">
+        <except>
+          <name>name</name>
+          <name>expand-text</name>
+          <name>use-when</name>
+        </except>
+      </nsName>
+    </attribute>
+  </define>
+  <define name="extension.attr">
+    <attribute>
+      <anyName>
+        <except>
+          <nsName ns=""/>
+          <nsName ns="http://www.w3.org/XML/1998/namespace"/>
+          <nsName/>
+        </except>
+      </anyName>
+    </attribute>
+  </define>
+  <define name="AnyElement" sa:model="anyElement">
+    <element>
+      <anyName/>
+      <zeroOrMore>
+        <choice>
+          <ref name="_any.attr"/>
+          <text/>
+          <ref name="AnyElement"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="AnyNonXProcElement" sa:model="anyNonXProcElement">
+    <element>
+      <anyName>
+        <except>
+          <nsName ns="http://www.w3.org/ns/xproc-step"/>
+          <nsName/>
+        </except>
+      </anyName>
+      <zeroOrMore>
+        <choice>
+          <ref name="_any.attr"/>
+          <text/>
+          <ref name="AnyElement"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="Any" sa:model="anyNode">
+    <choice>
+      <element>
+        <anyName/>
+        <zeroOrMore>
+          <choice>
+            <ref name="_any.attr"/>
+            <ref name="Any"/>
+          </choice>
+        </zeroOrMore>
+      </element>
+      <text/>
+    </choice>
+  </define>
+  <!-- ============================================================ -->
+  <define name="VocabParam" sa:class="step-vocabulary">
+    <element name="c:param">
+      <ref name="name.qname.attr"/>
+      <optional>
+        <attribute name="namespace">
+          <data type="anyURI"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="value"/>
+      </optional>
+      <optional>
+        <ref name="as.attr"/>
+      </optional>
+      <zeroOrMore>
+        <ref name="AnyElement"/>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="VocabParamSet" sa:class="step-vocabulary">
+    <element name="c:param-set">
+      <zeroOrMore>
+        <ref name="VocabParam"/>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="VocabDirectory" sa:class="step-vocabulary">
+    <element name="c:directory">
+      <attribute name="name"/>
+      <ref name="xmlbase.attr"/>
+      <ref name="file-info.attributes"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="VocabFile"/>
+          <ref name="VocabDirectory"/>
+          <ref name="VocabOther"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="VocabFile" sa:class="step-vocabulary">
+    <element name="c:file">
+      <attribute name="name"/>
+      <ref name="xmlbase.attr"/>
+      <ref name="file-info.attributes"/>
+      <optional>
+        <ref name="content-type.attr"/>
+      </optional>
+      <empty/>
+    </element>
+  </define>
+  <define name="VocabOther" sa:class="step-vocabulary">
+    <element name="c:other">
+      <attribute name="name"/>
+      <ref name="xmlbase.attr"/>
+      <ref name="file-info.attributes"/>
+      <empty/>
+    </element>
+  </define>
+  <define name="file-info.attributes">
+    <optional>
+      <ref name="size.attr"/>
+    </optional>
+    <optional>
+      <ref name="readable.attr"/>
+    </optional>
+    <optional>
+      <ref name="writable.attr"/>
+    </optional>
+    <optional>
+      <ref name="last-modified.attr"/>
+    </optional>
+    <optional>
+      <ref name="hidden.attr"/>
+    </optional>
+  </define>
+  <define name="size.attr">
+    <attribute name="size">
+      <data type="integer"/>
+    </attribute>
+  </define>
+  <define name="readable.attr">
+    <attribute name="readable">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="writable.attr">
+    <attribute name="writable">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="hidden.attr">
+    <attribute name="hidden">
+      <data type="boolean"/>
+    </attribute>
+  </define>
+  <define name="last-modified.attr">
+    <attribute name="last-modified">
+      <data type="dateTime"/>
+    </attribute>
+  </define>
+  <define name="VocabResult" sa:class="step-vocabulary">
+    <element name="c:result">
+      <text/>
+    </element>
+  </define>
+  <define name="VocabHttpRequest" sa:class="step-vocabulary">
+    <element name="c:request">
+      <attribute name="method">
+        <data type="NCName"/>
+      </attribute>
+      <optional>
+        <attribute name="href">
+          <data type="anyURI"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="detailed">
+          <data type="boolean"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="status-only">
+          <data type="boolean"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="username"/>
+      </optional>
+      <optional>
+        <attribute name="password"/>
+      </optional>
+      <optional>
+        <attribute name="auth-method"/>
+      </optional>
+      <optional>
+        <attribute name="send-authorization">
+          <data type="boolean"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="override-content-type">
+          <ref name="ContentType"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="timeout">
+          <data type="positiveInteger"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="fail-on-timeout">
+          <data type="boolean"/>
+        </attribute>
+      </optional>
+      <group>
+        <zeroOrMore>
+          <ref name="VocabHeader"/>
+        </zeroOrMore>
+        <optional>
+          <choice>
+            <ref name="VocabMultipart"/>
+            <ref name="VocabBody"/>
+          </choice>
+        </optional>
+      </group>
+    </element>
+  </define>
+  <define name="VocabHeader" sa:class="step-vocabulary">
+    <element name="c:header">
+      <attribute name="name"/>
+      <attribute name="value"/>
+      <empty/>
+    </element>
+  </define>
+  <define name="VocabMultipart" sa:class="step-vocabulary">
+    <element name="c:multipart">
+      <ref name="content-type.attr"/>
+      <attribute name="boundary"/>
+      <oneOrMore>
+        <ref name="VocabBody"/>
+      </oneOrMore>
+    </element>
+  </define>
+  <define name="VocabBody" sa:class="step-vocabulary">
+    <element name="c:body">
+      <ref name="content-type.attr"/>
+      <optional>
+        <attribute name="encoding"/>
+      </optional>
+      <optional>
+        <attribute name="id"/>
+      </optional>
+      <optional>
+        <attribute name="description"/>
+      </optional>
+      <optional>
+        <attribute name="disposition"/>
+      </optional>
+      <zeroOrMore>
+        <ref name="Any"/>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="VocabHttpResponse" sa:class="step-vocabulary">
+    <element name="c:response">
+      <optional>
+        <attribute name="status">
+          <data type="integer"/>
+        </attribute>
+      </optional>
+      <group>
+        <zeroOrMore>
+          <ref name="VocabHeader"/>
+        </zeroOrMore>
+        <optional>
+          <choice>
+            <ref name="VocabMultipart"/>
+            <ref name="VocabBody"/>
+          </choice>
+        </optional>
+      </group>
+    </element>
+  </define>
+  <define name="VocabQuery" sa:class="step-vocabulary">
+    <element name="c:query">
+      <text/>
+    </element>
+  </define>
+  <define name="VocabLine" sa:class="step-vocabulary">
+    <element name="c:line">
+      <text/>
+    </element>
+  </define>
+  <define name="VocabData" sa:class="step-vocabulary">
+    <element name="c:data">
+      <ref name="content-type.attr"/>
+      <optional>
+        <attribute name="charset"/>
+      </optional>
+      <optional>
+        <attribute name="encoding"/>
+      </optional>
+      <text/>
+    </element>
+  </define>
+  <define name="VocabArchive" sa:class="step-vocabulary">
+    <element name="c:archive">
+      <interleave>
+        <zeroOrMore>
+          <ref name="VocabEntry"/>
+        </zeroOrMore>
+        <zeroOrMore>
+          <ref name="AnyNonXProcElement"/>
+        </zeroOrMore>
+      </interleave>
+    </element>
+  </define>
+  <define name="VocabEntry" sa:class="step-vocabulary">
+    <element name="c:entry">
+      <attribute name="name"/>
+      <attribute name="href">
+        <data type="anyURI"/>
+      </attribute>
+      <optional>
+        <attribute name="comment"/>
+      </optional>
+      <optional>
+        <attribute name="method"/>
+      </optional>
+      <optional>
+        <attribute name="level"/>
+      </optional>
+      <optional>
+        <ref name="content-type.attr"/>
+      </optional>
+      <zeroOrMore>
+        <attribute>
+          <anyName>
+            <except>
+              <nsName ns=""/>
+              <nsName/>
+              <nsName ns="http://www.w3.org/ns/xproc-step"/>
+            </except>
+          </anyName>
+        </attribute>
+      </zeroOrMore>
+      <zeroOrMore>
+        <ref name="AnyElement"/>
+      </zeroOrMore>
+    </element>
+  </define>
+  <!-- ============================================================ -->
+  <define name="Errors" sa:class="error-vocabulary">
+    <element name="c:errors">
+      <zeroOrMore>
+        <ref name="Error"/>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="Error" sa:class="error-vocabulary">
+    <element name="c:error">
+      <optional>
+        <ref name="name.ncname.attr"/>
+      </optional>
+      <optional>
+        <attribute name="type">
+          <data type="QName"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="code">
+          <data type="QName"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="cause">
+          <data type="QName"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="href">
+          <data type="anyURI"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="line">
+          <data type="integer"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="column">
+          <data type="integer"/>
+        </attribute>
+      </optional>
+      <optional>
+        <attribute name="offset">
+          <data type="integer"/>
+        </attribute>
+      </optional>
+      <zeroOrMore>
+        <ref name="Any"/>
+      </zeroOrMore>
+    </element>
+  </define>
+  <define name="Charset">
+    <text/>
+  </define>
+  <define name="Encoding">
+    <text/>
+  </define>
+  <define name="MIMEContentType">
+    <text/>
+  </define>
+  <define name="MIMEMediaType">
+    <text/>
+  </define>
+  <define name="RegularExpression">
+    <text/>
+  </define>
+  <define name="NormalizationForm">
+    <choice>
+      <value>NFC</value>
+      <value>NFD</value>
+      <value>NFKC</value>
+      <value>NFKD</value>
+      <value>fully-normalized</value>
+      <value>none</value>
+      <data type="NMTOKEN"/>
+    </choice>
+  </define>
+  <define name="ListOfQNames">
+    <text/>
+  </define>
+</grammar>