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Grouping

The grouping operator ( ) controls the precedence of evaluation in expressions.

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

Using the grouping operator

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

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
Grouping operator () 1 12 1 3 3 1
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
Grouping operator () 1 18 4 10.1 1 1.0
Server
Node.js
Grouping operator () 0.1.100

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://wiki.developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Grouping