Boolean Values

Boolean: the last of the simple ones

>>> 1 < 2
>>> 'X' == 'U'
  • Values True and False

  • Result of comparison operators

  • Used with control flow statements (if, while)

  • ⟶ later

Boolean Operators

Usual operators

  • L and R: True if both L and R evaluate to True

  • L or R: True if L or R evaluate to True

  • not X: True if X evaluates to False

Short circuit evaluation: operands are only evaluated until the expression’s value is clear

  • L and R: if L is False, then the expression cannot become True anymore ⟶ R not evaluated

  • L or R: if L is True, …

  • ⟶ important when L, R are functions with side effects