30-seconds-of-code/snippets/index_of_all.md

title, tags, firstSeen, lastUpdated

title	tags	firstSeen	lastUpdated
index_of_all	list,intermediate	2020-10-11T13:40:42+03:00	2020-10-11T13:45:19+03:00

Returns a list of indexes of all the occurrences of an element in a list.

• Use enumerate() and a list comprehension to check each element for equality with value and adding i to the result.

def index_of_all(lst, value):
  return [i for i, x in enumerate(lst) if x == value]

index_of_all([1, 2, 1, 4, 5, 1], 1) # [0, 2, 5]
index_of_all([1, 2, 3, 4], 6) # []