30-seconds-of-code/snippets/python/s/none.md

title, type, language, tags, cover, dateModified

title	type	language	tags	cover	dateModified
Test if every list element is falsy	snippet	python	list	jars-on-shelf-2	2020-11-02T19:28:27+02:00

Checks if the provided function returns True for at least one element in the list.

• Use all() and fn to check if fn returns False for all the elements in the list.

def none(lst, fn = lambda x: x):
  return all(not fn(x) for x in lst)

none([0, 1, 2, 0], lambda x: x >= 2 ) # False
none([0, 0, 0]) # True