[IPython-user] pre/post-filters (was Evaluation of arbitrary expressions )

[Frédéric Mantegazza]

Le Mercredi 14 Septembre 2005 17:59, Fernando Perez a écrit :

> > Fernando, what about 2 additional hooks : one to execute arbitrary code
> > *before* the input string is executed, and one *after* ?
>
> They already exist :) They are called:
>
>
> In [3]: __IP.prefilter?
> Type:           instancemethod
> Base Class:     <type 'instancemethod'>
> String Form:    <bound method InteractiveShell._prefilter of
> <IPython.iplib.InteractiveShell instance at 0x40061e8c>>
> Namespace:      Interactive
> File:           /usr/local/home/fperez/code/python/IPython/iplib.py
> Definition:     __IP.prefilter(self, line, continue_prompt)
> Docstring:
>      Calls different preprocessors, depending on the form of line.
>
>
> In [4]: __IP.outputcache.display?
> Type:           instancemethod
> Base Class:     <type 'instancemethod'>
> String Form:    <bound method CachedOutput._display of
> <IPython.Prompts.CachedOutput instance at 0x403c0a2c>>
> Namespace:      Interactive
> File:           /usr/local/home/fperez/code/python/IPython/Prompts.py
> Definition:     __IP.outputcache.display(self, arg)
> Docstring:
>      Default printer method, uses pprint.
>
>      This can be over-ridden by the users to implement special formatting
>      of certain types of output.
>
> Display isn't very well documented (prefilter is, since the pysh and
> other examples show how to use it), but it's there.
> [...]
> Have a look at the pysh, tutorial or physics profiles :)

Oh, yes, I remember these hooks ! I planed to use prefilters to avoid the 
user deleting internal objects of our PyMAD project... I still have to do 
that :o/

-- 
   Frédéric