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

Eric Nieuwland eric.nieuwland at xs4all.nl
Sat Feb 4 09:05:37 CET 2006

Nick Coghlan wrote:
> That's like saying "it's not the same because '(x*x def (x)' creates a
> function while '(x*x for x in seq)' creates a generator-iterator". 
> Well,
> naturally - if the expression didn't do something different, what 
> would be the
> point in having it?
Naturally.  I just wanted to point out it's a beast of another kind, so 
like syntax may not be a good idea.

> The parallel I'm trying to draw is at the syntactic level, not the 
> semantic.
> I'm quite aware that the semantics will be very different ;)
>> Yours is
>> f = lambda x: x*x
>> and it will die by Guido hand...
> In the short term, probably. I'm hoping that the progressive 
> accumulation of
> workarounds like itemgetter, attrgetter and partial (and Alex's 
> suggestion of
> 'methodcaller') and the increasing use of function arguments for 
> things like
> sorting and the itertools module will eventually convince Guido that 
> deferring
> expressions is a feature that needs to be *fixed* rather than 
> discarded entirely.

Then how about nameless function/method definition:
	def (x):
		... usual body ...
produces an unnamed method object
	def spam(x):
is just
	spam = def (x):
while our beloved
	eggs(lambda x: x*x)
would become
	eggs(def(x): return x*x)


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