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