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Reference > Language > Structure > Boolean operators > Logicalnot

!

[Boolean Operators]

Description

Logical NOT results in a true if the operand is false and vice versa.

Example Code

This operator can be used inside the condition of an if statement.

if (!x) { // if x is not true
  // statements
}

It can be used to invert the boolean value.

x = !y; // the inverted value of y is stored in x

Notes and Warnings

The bitwise not ~ (tilde) looks much different than the boolean not ! (exclamation point or "bang" as the programmers say) but you still have to be sure which one you want where.

See also