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RegExp.prototype.toString()

The toString() method returns a string representing the regular expression.

Try it

Syntax

toString()

Return value

A string representing the given object.

Description

The RegExp object overrides the toString() method of the Object object; it does not inherit Object.prototype.toString(). For RegExp objects, the toString() method returns a string representation of the regular expression.

Examples

Using toString()

The following example displays the string value of a RegExp object:

var myExp = new RegExp('a+b+c');
console.log(myExp.toString());  // logs '/a+b+c/'

var foo = new RegExp('bar', 'g');
console.log(foo.toString());    // logs '/bar/g'

Empty regular expressions and escaping

Starting with ECMAScript 5, an empty regular expression returns the string "/(?:)/" and line terminators such as "\n" are escaped:

new RegExp().toString(); // "/(?:)/"

new RegExp('\n').toString() === '/\n/';  // true, prior to ES5
new RegExp('\n').toString() === '/\\n/'; // true, starting with ES5

Specifications

Browser compatibility

Desktop Mobile Server
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet Deno Node.js
toString
1
12
1
4
5
1
1
18
4
10.1
1
1.0
1.0
0.10.0
escaping
73
12
38
9
60
6
73
73
38
52
6
11.0
1.0
12.0.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/toString