The grouping operator
( ) controls the precedence of evaluation in expressions.
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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.
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
|ECMAScript Latest Draft (ECMA-262)
The definition of 'The Grouping Operator' in that specification.
|Grouping operator ||Chrome Full support 1||Edge Full support 12||Firefox Full support 1||IE Full support 3||Opera Full support Yes||Safari Full support 1||WebView Android Full support 1||Chrome Android Full support 18||Firefox Android Full support 4||Opera Android Full support Yes||Safari iOS Full support 1||Samsung Internet Android Full support 1.0||nodejs Full support Yes|
- Full support
- Full support