30-seconds-of-code/snippets/find-index-of-all.md

title, tags, cover, firstSeen, lastUpdated

title	tags	cover	firstSeen	lastUpdated
Find all matching indexes	list	tree-roots	2020-10-11T13:45:19+03:00	2020-11-02T19:27:53+02:00

Finds the indexes of all elements in the given list that satisfy the provided testing function.

• Use enumerate() and a list comprehension to return the indexes of the all element in lst for which fn returns True.

def find_index_of_all(lst, fn):
  return [i for i, x in enumerate(lst) if fn(x)]

find_index_of_all([1, 2, 3, 4], lambda n: n % 2 == 1) # [0, 2]