30-seconds-of-code/snippets/bifurcate-by.md

title, tags, cover, firstSeen, lastUpdated

title	tags	cover	firstSeen	lastUpdated
Bifurcate list based on function	list	two-flower-vases	2019-08-20T12:41:21+03:00	2020-11-02T19:27:07+02:00

Splits values into two groups, based on the result of the given filtering function.

• Use a list comprehension to add elements to groups, based on the value returned by fn for each element.
• If fn returns a truthy value for any element, add it to the first group, otherwise add it to the second group.

def bifurcate_by(lst, fn):
  return [
    [x for x in lst if fn(x)],
    [x for x in lst if not fn(x)]
  ]

bifurcate_by(['beep', 'boop', 'foo', 'bar'], lambda x: x[0] == 'b')
# [ ['beep', 'boop', 'bar'], ['foo'] ]