fixes #2

AnswerDotAI · Dec 16, 2024 · 7c81e33 · 7c81e33
1 parent 249f874
commit 7c81e33
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Showing 4 changed files with 204 additions and 5 deletions.
diff --git a/00_core.ipynb b/00_core.ipynb
@@ -103,8 +103,8 @@
      "output_type": "stream",
      "text": [
       "00_core.ipynb\r\n",
-      "LICENSE\r\n",
-      "MANIFEST.in\r\n",
+      "CHANGELOG.bak\r\n",
+      "CHANGELOG.md\r\n",
       "\n"
      ]
     }
@@ -169,8 +169,8 @@
      "output_type": "stream",
      "text": [
       "00_core.ipynb\r\n",
-      "LICENSE\r\n",
-      "MANIFEST.in\n"
+      "CHANGELOG.bak\r\n",
+      "CHANGELOG.md\n"
      ]
     }
    ],
@@ -280,6 +280,7 @@
     "    @no_var_expand\n",
     "    def psh(self, line, cell=None):\n",
     "        \"Run line or cell in persistent shell\"\n",
+    "        if not cell and not line: line = 'echo'\n",
     "        if cell: cell = shell_replace(cell, self.shell)\n",
     "        if line: line = shell_replace(line, self.shell)\n",
     "        args = self.psh.parser.parse_args(line.split())\n",
@@ -484,6 +485,47 @@
     "%psh ls | head -@{n}"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "3de04eee",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "starting\r\n",
+      "[1] 99418\n"
+     ]
+    }
+   ],
+   "source": [
+    "%%psh\n",
+    "echo starting\n",
+    "(sleep 1; echo finished) &"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "58be93c1",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "finished\r\n",
+      "\r\n",
+      "[1]+  Done                    ( sleep 1; echo finished )\n"
+     ]
+    }
+   ],
+   "source": [
+    "%psh"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,

diff --git a/README.md b/README.md
@@ -64,6 +64,8 @@ sourcing scripts, and changing directories.
 
 ## Features
 
+### Cell magic
+
 You can use the `%%psh` cell magic to run multi-line shell commands,
 such as here-docs. For instance:
 
@@ -88,6 +90,8 @@ rm tmp
     hi
     there
 
+### Variable expansion
+
 You can pipe commands together just like in a regular shell, and use
 standard unix utilities like `head` to process the output. For instance,
 here we show just the first 3 lines of the directory listing:
@@ -120,6 +124,50 @@ listing:
     ContextKit
     FastHTML-Gallery
 
+### Background tasks
+
+You can run commands in the background in the shell by adding `&` at the
+end of a command. The parentheses `(...)` group commands together to run
+as one unit. In this example, we first print “starting”, and then create
+a background process that will wait for 1 second (using `sleep 1`) and
+then print “finished”. The shell immediately shows us “starting” and
+tells us it created background process number 1 (with a process ID):
+
+``` python
+%%psh
+echo starting
+(sleep 1; echo finished) &
+```
+
+    starting
+    [1] 99418
+
+For this demonstration, we wait for 1.1 seconds (slightly longer than
+the background process needs). During this time, the background process
+will complete in the background. But we won’t see any output from it
+yet.
+
+``` python
+from time import sleep
+sleep(1.1)
+```
+
+The next time we run *any* `psh` magic we will also see any output that
+has occurred in our persistent shell since the last command. Run `%psh`
+by itself to *only* see those updates, e.g here we see that “finished”
+was printed, and the shell tells us that background job 1 completed
+successfully.
+
+``` python
+%psh
+```
+
+    finished
+
+    [1]+  Done                    ( sleep 1; echo finished )
+
+### Flags
+
 You can get help on the `%psh` magic’s options using `-h`.
 
 ``` python

diff --git a/index.ipynb b/index.ipynb
@@ -167,6 +167,14 @@
     "## Features"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "f723a8d0",
+   "metadata": {},
+   "source": [
+    "### Cell magic"
+   ]
+  },
   {
    "cell_type": "markdown",
    "id": "7458388b",
@@ -218,6 +226,14 @@
     "rm tmp"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "18dbf666",
+   "metadata": {},
+   "source": [
+    "### Variable expansion"
+   ]
+  },
   {
    "cell_type": "markdown",
    "id": "aa737da1",
@@ -301,7 +317,99 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c7acc94b",
+   "id": "09de8f02",
+   "metadata": {},
+   "source": [
+    "### Background tasks"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "e47e6917",
+   "metadata": {},
+   "source": [
+    "You can run commands in the background in the shell by adding `&` at the end of a command. The parentheses `(...)` group commands together to run as one unit. In this example, we first print \"starting\", and then create a background process that will wait for 1 second (using `sleep 1`) and then print \"finished\". The shell immediately shows us \"starting\" and tells us it created background process number 1 (with a process ID):"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "3de04eee",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "starting\r\n",
+      "[1] 99418\n"
+     ]
+    }
+   ],
+   "source": [
+    "%%psh\n",
+    "echo starting\n",
+    "(sleep 1; echo finished) &"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "dd6fde98",
+   "metadata": {},
+   "source": [
+    "For this demonstration, we wait for 1.1 seconds (slightly longer than the background process needs). During this time, the background process will complete in the background. But we won't see any output from it yet."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "97498951",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from time import sleep\n",
+    "sleep(1.1)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "fc7a24c6",
+   "metadata": {},
+   "source": [
+    "The next time we run *any* `psh` magic we will also see any output that has occurred in our persistent shell since the last command. Run `%psh` by itself to *only* see those updates, e.g here we see that \"finished\" was printed, and the shell tells us that background job 1 completed successfully."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "58be93c1",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "finished\r\n",
+      "\r\n",
+      "[1]+  Done                    ( sleep 1; echo finished )\n"
+     ]
+    }
+   ],
+   "source": [
+    "%psh"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "69f0197a",
+   "metadata": {},
+   "source": [
+    "### Flags"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "c8314764",
    "metadata": {},
    "source": [
     "You can get help on the `%psh` magic's options using `-h`."

diff --git a/pshnb/core.py b/pshnb/core.py
@@ -85,6 +85,7 @@ def _timeout(self, timeout=2):
     @no_var_expand
     def psh(self, line, cell=None):
         "Run line or cell in persistent shell"
+        if not cell and not line: line = 'echo'
         if cell: cell = shell_replace(cell, self.shell)
         if line: line = shell_replace(line, self.shell)
         args = self.psh.parser.parse_args(line.split())