Re: [PATCH] Add optional dependencies to ipython.

[Ricardo Wurmus <ricardo.wurmus@mdc-berlin.de>]

>> From 9243823abad3943bd3f4ebe4f6d18cc53c2143e0 Mon Sep 17 00:00:00 2001
>> From: Ricardo Wurmus <ricardo.wurmus@mdc-berlin.de>
>> Date: Thu, 21 May 2015 15:24:11 +0200
>> Subject: [PATCH] gnu: python-ipython: Add optional dependencies.
>>
>> * gnu/packages/python.scm (python-ipython)[inputs]: Add optional dependencies
>>   "python-tornado" and "python-pyzmq".
>
> LGTM.  One question though: how much does it add to the ipython’s
> closure size, and is it something that many ipython users would have
> little use for?
>
> IOW, the popularity/extra-space ratio should be greater than one.  :-)

Before the patch:

  du -ms $(guix gc -R \
    /gnu/store/frjwvppazzjvp7pzwfawa9nrq1nx135q-python-ipython-2.3.1) | \
    cut -f1 | paste -s -d+ | bc

  ==> 683 MB

After the patch:

  du -ms $(guix gc -R \
    /gnu/store/bqpmsh45fzmjynczcwx6zvycinf7c91r-python-ipython-2.3.1) | \
    cut -f1 | paste -s -d+ | bc

  ==> 765 MB

I don't know if support for python-tornado and python-pyzmq in
python-ipython is worth an additional 82 MB.

It was only after I packaged python-tornado and python-pyzmq for other
purposes that I noticed that python-ipython takes it as an optional
input, so I added it.  (Personally, I don't need it because I'm not an
IPython user.)

~~ Ricardo