The decrement operator (--
) decrements (subtracts one from) its operand and returns a value.
Decrement (--)
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Syntax
x-- --x
Description
If used postfix, with operator after operand (for example, x--
), the decrement operator decrements and returns the value before decrementing.
If used prefix, with operator before operand (for example, --x
), the decrement operator decrements and returns the value after decrementing.
Examples
Postfix decrement
let x = 3; y = x--; // y = 3 // x = 2
Prefix decrement
let a = 2; b = --a; // a = 1 // b = 1
Specifications
Browser compatibility
Desktop | Mobile | Server | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | Deno | Node.js | |
Decrement |
2
|
12
|
1
|
3
|
3
|
4
|
1
|
18
|
4
|
10.1
|
3.2
|
1.0
|
1.0
|
0.10.0
|
See also
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Decrement