def test_Nothing_filter():
assert Nothing.filter(lambda x: x > 4) is Nothing
def test_Nothing_get_or():
assert Nothing.get_or(3) == 3
def test_Nothing_fmap():
assert Nothing.fmap(add_two) is Nothing
def test_Nothing_apply():
assert Nothing.apply(add_two) is Nothing
def test_Maybe_to_Either():
assert Just(4).to_either(None) == Right(4)
assert Nothing.to_either('failure') == Left('failure')
def test_Nothing_chain_many():
x = Nothing.or_call(add_two, 2).filter(lambda x: x & 1)
assert x is Nothing
def test_Nothing_or_call():
assert Nothing.or_call(add_two, 2) == Just(4)
def test_Nothing_or_else():
assert Nothing.or_else(4) == Just(4)
def test_Nothing_get_or_call():
assert Nothing.get_or_call(add_two, 2) == 4