Logical NOT Operator (!)
Performs logical negation on an expression.
result = !expression
Arguments
- result
- Any variable.
- expression
- Any expression.
Remarks
The following table illustrates how result is determined.
If expression is | 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.
Requirements
See Also
~ Operator | Operator Precedence | Operator Summary
