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

Christian Tismer tismer at stackless.com
Fri Feb 3 19:10:42 CET 2006


Bengt Richter wrote:

...

> BTW, re def-time bindings, the default arg abuse is a hack, so I would like to
> see a syntax that would permit default-arg-like def-time function-local bindings without
> affecting the call signature. E.g., if def foo(*args, **keywords, ***bindings): ...
> would use bindings as a dict at def-time to create local namespace bindings like **keywords,
> but not affecting the call signature. This would allow a nicer version of above-mentioned
>    lambda x, zip=zip, zop=zop:x.method(zip,zop)
> as
>    lambda x, ***dict(zip=zip, zop=zop):x.method(zip,zop)
> or
>    lambda x, ***{'zip':zip, 'zop':zop}:x.method(zip,zop)
> This could also be used to do currying without the typical cost of wrapped nested calling.

Just in case that you might be not aware of it (like I was):
lambda does support local scope, like here:

 >>> def locallambda(x, y):
... 	func = lambda: x+y
... 	return func
...
 >>> f=locallambda(2, 3)
 >>> f()
5
 >>>

ciao - chris

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