generic function that calls others

[msteinore]

I want to write a generic function that calls other functions and does some additional pre and post processing.

Example calls:

genericfn(funct ion=max,a=3,b=4 ) would call max(a=3,b=4) and return 4
genericfn(funct ion=average,a=4 ,c=8) would call average(a=4,c=8 ) and return 6, assuming parameter b in fn average defaults to 6

It should handle any user-defined function with a variable number of keyword args.
Here's the code I have so far, but I don't know how to get the dictionary to convert to a series of keyword args.

def genericfn(*args ,**kwargs):
fnToApply = kwargs['function']
del kwargs['function']
return fnToApply(args, kwargs)

Thanks for your help.

[bvdet]

I want to write a generic function that calls other functions and does some additional pre and post processing.

Example calls:

genericfn(funct ion=max,a=3,b=4 ) would call max(a=3,b=4) and return 4
genericfn(funct ion=average,a=4 ,c=8) would call average(a=4,c=8 ) and return 6, assuming parameter b in fn average defaults to 6

It should handle any user-defined function with a variable number of keyword args.
Here's the code I have so far, but I don't know how to get the dictionary to convert to a series of keyword args.

def genericfn(*args ,**kwargs):
fnToApply = kwargs['function']
del kwargs['function']
return fnToApply(args, kwargs)

Thanks for your help.

Something like this:

import operator
 
def genericfn(*args,**kwargs):
    fnToApply = kwargs['function']
    del kwargs['function']
    return fnToApply(*args)
 
dd = {'function': max}
print genericfn(1,2,3,4,5,**dd)
 
dd = {'function': operator.mul}
print genericfn(7,9,**dd)

>>> 5
63
>>>

[elcron]

def someFunction(*args, **kwargs):
    "someFunction"
    print 'args:   ',args
    print 'kwargs: ',kwargs
 
def factoryFunction(func, *args, **kwargs):
    print 'Starting %s'%func.__doc__  # code before
    values = func(*args, **kwargs)
    print 'Finishing %s'%func.__doc__ # code after
    return values
 
>>> factoryFunction(someFunction, 1,2,3,['a','list'], greeting='hello', number=1)
Starting someFunction
args:    (1, 2, 3, ['a', 'list'])
kwargs:  {'greeting': 'hello', 'number': 1}
Finishing someFunction
 
>>> args = (someFunction, 1,2,3,['a','list'])
>>> kwargs = {'greeting':'hello', 'number':1}
>>> factoryFunction(*args, **kwargs)
Starting someFunction
args:    (1, 2, 3, ['a', 'list'])
kwargs:  {'greeting': 'hello', 'number': 1}
Finishing someFunction
 

'*' creates a tuple of all extra the values and '*' can also turn a tuple back into arguments
'**' creates a dictionary of all the extra keywords and '**' can also turn a dictionary back into keywords
I would recommend requiring the function be passed in and save yourself the trouble of having to extract and remove it.