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A good example to explain *args and **kwargs in python

March 10th, 2009
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I read this wonderful example here: http://www.megasolutions.net/python/-args-and—kwargs-78766.aspx

>>> def a(*stuff):
                 print repr(stuff)
>>> def b(**stuff):
                 print repr(stuff)
>>> def c(*args, **kwargs):
                 print 'args', repr(args)
                 print 'kwargs', repr(kwargs)
>>> a(1,2,3)
(1, 2, 3)
>>> b(hello='world', lingo='python')
{'hello': 'world', 'lingo': 'python'}
>>> c(13,14,thenext=16,afterthat=17)
args (13, 14)
kwargs {'afterthat': 17, 'thenext': 16}
>>> args = [1,2,3,4]
>>> kwargs = {'no-way': 23, 'yet-anotherInvalid.name': 24}
>>> c(*args, **kwargs)
args (1, 2, 3, 4)
kwargs {'no-way': 23, 'yet-anotherInvalid.name': 24}

Here is some simple explaination about *args and **kwargs

Basically ‘args’ is a tuple with all the positional arguments, kwargs is a dictionary with all the named arguments.
Likewise you can pass a tuple to a function like func(*tuple), or a dict like func(**dictionary) or both, where the zuple has to come first.

Python

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