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[email protected]@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

Browser compatibilityUpdate compatibility data on GitHub

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

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/Global_Objects/RegExp/@@search