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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 whats 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

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)
Feature Android Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

See also

© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Grouping