IPython in Emacs. Quick code evaluation

6
votes

Update: The question still lacks a satisfactory answer.

I would like to "send" code snippets to a IPython interpreter in Emacs 23.2 (Linux). Assuming that I have already started an IPython shell in a buffer in Emacs (e.g. using Python-mode.el and IPython.el), is there a way of selecting a region in a different buffer and "sending" this region to the already-started IPython shell?

I have tried C-c C-c (send-buffer-to-shell) and C-c | (send-region-to-shell), but this only works as long as the code is written in Python and not in IPython (IPython can run Python code). The reason seems to be that, for both commands, Emacs creates a temporary file with .py extension (as opposed to with .ipy extension), which then is interpreted by IPython as "Python-specific code". This prevents me from using IPython-specific features such as magic commands.

On a separate note, I have also read that Emacs provides M-| ('shell-command-on-region') to run selected regions in a shell. To do this with an IPython interpreter, I have tried setting shell-file-name to my IPython path. However, when I run M-| after selecting a region, Emacs prompts me the following:

Shell command on region:

and if I then type RET, I get the IPython man page on the *Shell Command Output* buffer, without the region being executed. Is there any IPython-specific command that I can use for M-| ('shell-command-on-region') to get IPython run my code?

Thanks!

2
pythonshellemacsipython
Assuming you can run ipython directly, I suspect you actually want to leave shell-file-name alone, and simply enter the ipython executable name at the prompt. That's the normal usage for shell-command-on-region, at any rate. The minibuffer history will remember that command, so you can easily repeat it with M-| M-p RET. I'm not sure how call-process-region works, but I imagine it sends the region text to the command as stdin, so as long as the ipython command can deal with receiving a script that way, I would think it ought to work (although if not, it might account for the help text). - phils
Thank you phils, that solution works, but it requires opening starting a new IPython shell (which takes some time to start) every time I need to test a code snippet - Amelio Vazquez-Reina

2 Answers

1
votes

Are you using ipython.el? It should work okay with Emacs 23.

If not, have a look at EmacsWiki: iPython Emacs 23.

There is also a section in the IPython Cookbook on Emacs (search for IPythonEmacs23; sorry am not allowed to post more than one link :(

Once you've started an ipython-shell (C-c !) you can execute code snippets from regions of any buffer in this already started shell using "Execute region ("C-c |")

Andreas

0
votes

I found a partial answer to Q1:

Python-mode provides C-c C-c which can send a buffer to an already-opened Python shell (similarly C-c C-| can send a region to the shell), and if ipython.el is installed, then default python shell is set to IPython.

Unfortunately, this only works for python scripts, and not for IPython scripts. C-c C-c works by copying the buffer with the code snippet to a temporary file with extension .py that is then sent to the shell. Since the file has extension .py IPython executes it as if it was regular Python code, and therefore the code snippet cannot have IPython-specific code (such as IPython magic commands)..