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The grouping operator ( )
controls the precedence of evaluation in expressions.
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Syntax
( )
Description
The grouping operator consists of a pair of parentheses around an expression or sub-expression to override the normal operator precedence so that expressions with lower precedence can be evaluated before an expression with higher priority. As it sounds it groups what's inside of the parentheses.
Examples
Overriding multiplication and division first, then addition and subtraction to evaluate addition first.
var a = 1; var b = 2; var c = 3; // default precedence a + b * c // 7 // evaluated by default like this a + (b * c) // 7 // now overriding precedence // addition before multiplication (a + b) * c // 9 // which is equivalent to a * c + b * c // 9
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript Latest Draft (ECMA-262) The definition of 'The Grouping Operator' in that specification. |
Draft | |
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'The Grouping Operator' in that specification. |
Standard | |
ECMAScript 5.1 (ECMA-262) The definition of 'The Grouping Operator' in that specification. |
Standard | |
ECMAScript 1st Edition (ECMA-262) The definition of 'The Grouping Operator' in that specification. |
Standard | Initial definition. Implemented in JavaScript 1.0. |
Browser compatibility
Feature | Chrome | Edge | Firefox | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|---|
Basic support | Yes | Yes | 1 | Yes | Yes | Yes |
Feature | Android webview | Chrome for Android | Edge mobile | Firefox for Android | Opera Android | iOS Safari | Samsung Internet |
---|---|---|---|---|---|---|---|
Basic support | Yes | Yes | Yes | 4 | Yes | Yes | Yes |