Partially evaluated functions

Nick Perkins nperkins7 at home.com
Thu Jun 21 05:51:34 CEST 2001


Rainer Deyke:
> > >>> def f(self, **kwargs):
> > ...   print self, kwargs
> > ...
> > >>> f(f, self=5)
> > Traceback (most recent call last):
> >   File "<stdin>", line 1, in ?
> > TypeError: keyword parameter redefined: self


Carsten Geckeler:

> Probably you mean
> curry(f, self=5)
> and not
> f(f, self=5)
>
> But you are right that you get a TypeError due to the __init__ function in
> the class.


Of course you get an error when you try to pass a keyword argument to a
function that does not take any keyword arguments.
( and why are you trying to pass 'self'?)


What does work, for the cookbook version, and Alex's functional version, is
any of the following:

def print_thing( thing='boat' )
    print thing
print_plane = curry( print_thing, thing='plane' )
print_plane()

..now calling print_plane() will simply print 'plane'


or, the same thing without the keywords:

def print_thing( thing ):
    print thing
print_plane = curry( print_thing, 'plane' )
print_plane()


or.. you can even do this:

def print_thing( thing='boat' ):
    print thing
print_plane = curry( print_thing, 'plane' )
print_plane()

..with a positional arg being 'promoted' to a keyword arg.






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