all()
Returns True
if every item in an iterable evaluates to True
, otherwise, it returns False
.
Syntax
all(iterable)
Example 1
As long as one element in the iterable is False
, all()
will return False
.
my_list = [True, "hello", 17]print(all(my_list))# Output: Truemy_list = [False, "hello", 17]print(all(my_list))# Output: False
Example 2
If the iterable is empty, all()
will return True
.
my_list = []print(all(my_list))# Output: True
The integer 0
evaluates to False
; however, all non-zero numbers and strings evaluate to True
.
my_list = [4, 3, 2, 1, 0]print(all(my_list))# Output: Falsemy_list = [4, 3, 2, 1, "0"]print(all(my_list))# Output: True
Different Types of Iterables
all()
can be used on any iterable, such as a list, set, string, dictionary, or tuple.
Lists
my_list = [1, 1, 0, True]print(all(my_list))# Output: False
This is False
because the integer 0
is False
.
Sets
my_set = {1, "False", True, 7}print(all(my_set))# Output: True
This is True
because strings and non-zero integers are True
.
Strings
my_string = "Python is more fun than Javascript"print(all(my_string))# Output: True
This is True
because strings and non-zero integers are True
.
Dictionaries
When all()
is used with a dictionary, it evaluates the keys, not the values. That means, even if a value is False
, all()
will return True
if all of the keys evaluate to True
.
my_dict = {0: "zero", 1: "one", 2: "two"}print(all(my_dict))# Output: False
This is False
because the first key, 0
, is False
.
Tuples
my_tuple = ("Heffalumps", "and", "Woozles")print(all(my_tuple))# Output: True
This is True
because all items in the tuple are True
.