any() function in Python with a callback

python functional-programming callback any
Emil Ivanov picture Emil Ivanov · Jan 6, 2010 · Viewed 76.5k times · Source

The Python standard library defines an any() function that

Return True if any element of the iterable is true. If the iterable is empty, return False.

It checks only if the elements evaluate to True. What I want it to be able so specify a callback to tell if an element fits the bill like:

any([1, 2, 'joe'], lambda e: isinstance(e, int) and e > 0)

Answer

Antoine P. picture Antoine P. · Jan 6, 2010

How about:

>>> any(isinstance(e, int) and e > 0 for e in [1,2,'joe'])
True

It also works with all() of course:

>>> all(isinstance(e, int) and e > 0 for e in [1,2,'joe'])
False

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