The decrement operator (--
) decrements (subtracts one from) its operand and returns a value.
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Syntax
Operator: x-- or --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
Specification |
---|
ECMAScript (ECMA-262) The definition of 'Decrement operator' in that specification. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Decrement (-- ) | Chrome Full support 2 | Edge Full support 12 | Firefox Full support 1 | IE Full support 3 | Opera Full support 3 | Safari Full support 4 | WebView Android Full support 1 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support 10.1 | Safari iOS Full support 3.2 | Samsung Internet Android Full support 1.0 | nodejs Full support 0.1.100 |
Legend
- Full support
- Full support