[Python-Dev] any support for a methodcaller HOF?

[Michael Hudson]

Jean-Paul Calderone <exarkun at divmod.com> writes:

> On Fri, 3 Feb 2006 07:00:26 -0800, Alex Martelli <aleaxit at gmail.com> wrote:
>>
>>On Feb 3, 2006, at 6:47 AM, Giovanni Bajo wrote:
>>    ...
>>> use itemgetter and friends but the "correct" way of doing a
>>> defferred "x[1]"
>>> *should* let you write "x[1]" in the code. This is my main
>>> opposition to
>>> partial/itemgetter/attrgetter/methodcaller: they allow deferred
>>> execution
>>> using a syntax which is not equivalent to that of immediate execution.
>>
>>I understand your worry re the syntax issue.  So what about Michael
>>Hudson's "placeholder class" idea, where X[1] returns the callable
>>that will do x[1] when called, etc?  Looks elegant to me...

I'd just like to point out here that I only mentioned this class; I
didn't suggest it for anything :)

> FWIW,
>
> <http://cvs.twistedmatrix.com/cvs/sandbox/glyph/eacher.py?view=markup&rev=12804>
> <http://cvs.twistedmatrix.com/cvs/sandbox/cake.py?view=markup&rev=12804>

Yow.  My implementation was somewhere in between those for length, I
think (and pre-dated new style classes, which probably changes
things).

Cheers,
mwh

-- 
  I'm sorry, was my bias showing again? :-)
                                      -- William Tanksley, 13 May 2000