Representation

Documentation

There are two boolean values supported by Elixir: true and false. There is, however, one more value that in the context of logical operations acts as false. This value is nil. Any value that is not nil or false will be treated as true.

You can check if given value is boolean with is_boolean/1 function:

iex> is_boolean 1
false
iex> is_boolean true
true

Logical operators

Boolean operators

The following operator requires the first argument to be either true or false.

a or b -> if the first argument is true then true, otherwise b
a and b -> if the first argument is true then b, otherwise false
not a -> if the argument is true then false, otherwise true

Relaxed boolean operators

Unlike previously introduced operators, relaxed boolean operators work with arguments of any type.

a || b -> if the first argument is true then a, otherwise b
a && b -> if the first argument is true then b, otherwise a
!a -> if the argument is true then false, otherwise true