Python equivalent of LINQ All function?

Question

What is the idiomatic Python way to test if all elements in a collection satisfy a condition? (The .NET All() method fills this niche nicely in C#.)

There's the obvious loop method:

all_match = True
for x in stuff:
    if not test(x):
        all_match = False
        break

And a list comprehension could do the trick, but seems wasteful:

all_match = len([ False for x in stuff if not test(x) ]) > 0

There's got to be something more elegant... What am I missing?

See also http://stackoverflow.com/questions/8641008/compare-multiple-variables-to-the-same-value-in-if-in-python — Karl Knechtel, Dec 27 '11 at 06:48

DSM · Accepted Answer · 2011-12-27T04:29:32.343

28

all_match = all(test(x) for x in stuff)

This short-circuits and doesn't require stuff to be a list -- anything iterable will work -- so has several nice features.

There's also the analogous

any_match = any(test(x) for x in stuff)

edited Dec 27 '11 at 04:29

answered Dec 27 '11 at 04:19

DSM

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Definitely the way I'd go. However, `all` in Python differs from `Enumerable.All` in that it does not directly take a predicate. (So it's more akin to `Enumerable.Where(predicate).All()`.) – Dec 27 '11 at 04:45

Python equivalent of LINQ All function?

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