Web/JavaScript/Reference/Global objects/RegExp/@@search

The [@@search]() method executes a search for a match between a this regular expression and a string.

Syntax

regexp[Symbol.search](str)

Parameters

str: A String that is a target of the search.

Return value

integer: If successful, [@@search]() returns the index of the first match of the regular expression inside the string. Otherwise, it returns -1.

Description

This method is called internally in String.prototype.search(). For example, the following two examples return the same result.

'abc'.search(/a/);

/a/[Symbol.search]('abc');

This method exists for customizing the search behavior in RegExp subclasses.

Examples

Direct call

This method can be used in almost the same way as String.prototype.search(), except the different this and the different arguments order.

var re = /-/g;
var str = '2016-01-02';
var result = re[Symbol.search](str);
console.log(result);  // 4

Using @@search in subclasses

Subclass of RegExp can override [@@search]() method to modify the behavior.

class MyRegExp extends RegExp {
  constructor(str) {
    super(str)
    this.pattern = str;
  }
  [Symbol.search](str) {
    return str.indexOf(this.pattern);
  }
}

var re = new MyRegExp('a+b');
var str = 'ab a+b';
var result = str.search(re); // String.prototype.search calls re[@@search].
console.log(result); // 3

Specifications

Specification
ECMAScript (ECMA-262)The definition of 'RegExp.prototype[@@search' in that specification.]

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
`@@search`	Chrome Full support 50	Edge Full support 13	Firefox Full support 49	IE No support No	Opera Full support 37	Safari Full support 10	WebView Android Full support 50	Chrome Android Full support 50	Firefox Android Full support 49	Opera Android Full support 37	Safari iOS Full support 10	Samsung Internet Android Full support 5.0	nodejs Full support 6.0.0

Legend

Full support: Full support
No support: No support