[IPython-dev] Small config puzzle

[Fernando Perez]

On Sun, Jun 3, 2012 at 4:35 PM, Brian Granger <ellisonbg at gmail.com> wrote:
> Doing so will add 1) docuemenation and 2) typing.  Putting things into
> dicts removes many of the benefits of our config system.

Though keep in mind that in this case we're forwarding data to
matplotlib, so I don't think we should be in the business of
documenting each of those keys from their docs.  For the entire rc
object we can say 'Dict of options for matplotlib', but if we handle
each field by hand, we'd be essentially duplicating the matplotlib
docs and type info (and possibly going out of sync with them).

Plus, it then means we have to manually add code to sync each of these
values with the corresponding key in the mpl rc structure.  We'll have
say

c.InlineBackend.rc_savefig_dpi = 99

and then will need to manually update

plt.rcParams['savefig.dpi'] = ...rc_savefig_dpi

once for each field.  Right now we simply do plt.rcParams.update(c.rc)
and we're done.

Granted, since we're only handling a few keys this way the boilerplate
isn't too terrible, but I wouldn't want to write such code for all the
matplotlib options :)

The alternative is to tell users to first initialize the value with
the dict/list by importing the class object from our own code:

from IPython.core... import InlineBackend

c.InlineBackend.rc = InlineBackend.rc.copy()
c.InlineBackend.rc['foo'] = 'bar'


Each solution has some drawbacks, I'm not sure right now which are worse...

Cheers,

f