Merge pull request #1146 from minrk/savescript

Allow saving notebook.py next to notebook.ipynb.  This allows notebooks to be imported or %run via their .py companion file.

IPython/frontend/html/notebook/notebookmanager.py

@@ -25,7 +25,7 b' from tornado import web'
 
 from IPython.config.configurable import LoggingConfigurable
 from IPython.nbformat import current
-from IPython.utils.traitlets import Unicode, List, Dict
+from IPython.utils.traitlets import Unicode, List, Dict, Bool
 
 
 #-----------------------------------------------------------------------------
@@ -38,6 +38,15 b' class NotebookManager(LoggingConfigurable):'
     notebook_dir = Unicode(os.getcwd(), config=True, help="""
         The directory to use for notebooks.
     """)
+    
+    save_script = Bool(False, config=True,
+        help="""Also save notebooks as a Python script.
+        
+        For easier use of import/%loadpy across notebooks, a <notebook-name>.py
+        script will be created next to any <notebook-name>.ipynb on each save.
+        """
+    )
+    
     filename_ext = Unicode(u'.ipynb')
     allowed_formats = List([u'json',u'py'])
 
@@ -197,12 +206,25 b' class NotebookManager(LoggingConfigurable):'
         try:
             with open(path,'w') as f:
                 current.write(nb, f, u'json')
-        except:
-            raise web.HTTPError(400, u'Unexpected error while saving notebook')
+        except Exception as e:
+            raise web.HTTPError(400, u'Unexpected error while saving notebook: %s' % e)
+        # save .py script as well
+        if self.save_script:
+            pypath = os.path.splitext(path)[0] + '.py'
+            try:
+                with open(pypath,'w') as f:
+                    current.write(nb, f, u'py')
+            except Exception as e:
+                raise web.HTTPError(400, u'Unexpected error while saving notebook as script: %s' % e)
+        
         if old_name != new_name:
             old_path = self.get_path_by_name(old_name)
             if os.path.isfile(old_path):
                 os.unlink(old_path)
+            if self.save_script:
+                old_pypath = os.path.splitext(old_path)[0] + '.py'
+                if os.path.isfile(old_pypath):
+                    os.unlink(old_pypath)
             self.mapping[notebook_id] = new_name
             self.rev_mapping[new_name] = notebook_id
 

docs/source/interactive/htmlnotebook.txt

@@ -188,6 +188,14 b' prior to import, you manually add the ``# <nbformat>2</nbformat>`` marker at'
 the start and then add separators for text/code cells, you can get a cleaner
 import with the file broken into individual cells.
 
+If you want use notebooks as scripts a lot, then you can set::
+
+    c.NotebookManager.save_script=True
+
+which will instruct the notebook server to save the ``.py`` export of each
+notebook adjacent to the ``.ipynb`` at every save.  Then these can be ``%run``
+or imported from regular IPython sessions or other notebooks.
+
 .. warning::
 
    While in simple cases you can roundtrip a notebook to Python, edit the