Python Boolean Operations

Python Boolean Operations
0

#1

and, or, not

Python Docs - Boolean Operations

These are the Boolean operations, ordered by ascending priority:

Operation Result Notes
x or y if x is false, then y, else x (1)
x and y if x is false, then x, else y (2)
not x if x is false, then True, else False (3)

Notes:

  1. This is a short-circuit operator, so it only evaluates the second argument if the first one is False.
  2. This is a short-circuit operator, so it only evaluates the second argument if the first one is True.
  3. not has a lower priority than non-Boolean operators, so not a == b is interpreted as not (a == b), and a == not b is a syntax error.

Examples:

not:

>>> not True
False
>>> not False
True

and:

>>> True and False    # Short-circuited at first argument.
False
>>> False and True    # Second argument is evaluated.
False
>>> True and True     # Second argument is evaluated.
True

or:

>>> True or False    # Short-circuited at first argument.
True
>>> False or True    # Second argument is evaluated.
True
>>> False or False   # Second argument is evaluated.
False

#2