24 lines
722 B
Python
24 lines
722 B
Python
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# pylint: disable=missing-docstring,invalid-name,no-absolute-import
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import functools
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# Don't do this, use a comprehension instead.
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assert map(lambda x: x*2, [1, 2, 3]) == [2, 4, 6] # [deprecated-lambda]
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assert filter(lambda x: x != 1, [1, 2, 3]) == [2, 3] # [deprecated-lambda]
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# It's still ok to use map and filter with anything but an inline lambda.
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double = lambda x: x * 2
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assert map(double, [1, 2, 3]) == [2, 4, 6]
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# It's also ok to pass lambdas to other functions.
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assert functools.reduce(lambda x, y: x * y, [1, 2, 3, 4]) == 24
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# Or to a undefined function or one with varargs
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def f(*a):
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return len(a)
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f(lambda x, y: x + y, [1, 2, 3])
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undefined_function(lambda: 2) # pylint: disable=undefined-variable
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