Logical NOT Operator (!)


!expression

The following table illustrates how the result is determined.

If `expression` coerces to	Then `result` is
true	false
false	true

All unary operators, such as the ! operator, evaluate expressions as follows:

If applied to undefined or null expressions, a run-time error is raised.
Objects are converted to strings.
Strings are converted to numbers if possible. If not, a run-time error is raised.
Boolean values are treated as numbers (0 if false, 1 if true).

The operator is applied to the resulting number.

For the ! operator, if expression is nonzero, result is zero. If expression is zero, result is 1.

Arguments