Pythonic way to check if: all elements evaluate to False -OR- all elements evaluate to True

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Chapters
00:00 Pythonic Way To Check If: All Elements Evaluate To False -Or- All Elements Evaluate To True
00:34 Answer 1 Score 11
00:46 Accepted Answer Score 24
00:53 Answer 3 Score 3
01:11 Answer 4 Score 2
01:16 Thank you

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Full question
https://stackoverflow.com/questions/4310...

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Tags
#python

#avk47

ACCEPTED ANSWER

Score 24

def unanimous(it):
  it1, it2 = itertools.tee(it)
  return all(it1) or not any(it2)

ANSWER 2

Score 11

def all_bools_equal(lst):
    return all(lst) or not any(lst)

See: http://docs.python.org/library/functions.html#all

See: http://docs.python.org/library/functions.html#any

ANSWER 3

Score 3

Piggybacking on Ignacio Vasquez-Abram's method, but will stop after first mismatch:

def unanimous(s):
  it1, it2 = itertools.tee(iter(s))
  it1.next()
  return not any(bool(a)^bool(b) for a,b in itertools.izip(it1,it2))

While using not reduce(operators.xor, s) would be simpler, it does no short-circuiting.

ANSWER 4

Score 2

def all_equals(xs):
    x0 = next(iter(xs), False)
    return all(bool(x) == bool(x0) for x in xs)