Parameterized Functions without Classes

Peter Otten __peter__ at web.de
Fri Jun 25 23:32:04 CEST 2004


Christopher T King wrote:

> On Fri, 25 Jun 2004, Christian Tismer wrote:
> 
>> Lambdas were not the topic, since they are a deprecated
>> feature, but sure it works.
> 
> Since when are lambdas deprecated? And if so, why?
> 
> IMHO, the best way to parameterize functions is with 2.4's proposed
> partial() function:
> 
> def converter(factor,val):
>     return val*factor
> 
> inchtocm=partial(converter,2.54)
> cmtoinch=partial(converter,1/2.54)
> 
> where a handy pre-2.4 definition of partial is:
> 
> def partial(func,*args,**kw):
>     return lambda *a,**k: func(*(args+a),**dict(kw.items()+k.items()))

In what way is that different from using an ordinary function? 

def partial(func, *args, **kw):
    def call(*a, **k): 
        return func(*(args+a), **dict(kw.items()+k.items()))    
    return call

Of course, the use of functions is not limited like lambdas
because (fortunately) they can contain more than one single
expression. But other than that, it's pretty much the
same concept, isn't it?

:-)

My-newsreader-doesn't-support-circular-threads-yetly yours,
Peter





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