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    RegExp.prototype.toString()

    Summary

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

    Syntax

    regexObj.toString();

    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

    Example: 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'
    

    Example: 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

    Specification Status Comment
    ECMAScript 3rd Edition. Standard Initial definition. Implemented in JavaScript 1.1.
    ECMAScript 5.1 (ECMA-262)
    The definition of 'RegExp.prototype.toString' in that specification.
    Standard Added definition for escaping behavior and "(?:)" for empty regular expressions.
    ECMAScript 6 (ECMA-262)
    The definition of 'RegExp.prototype.toString' in that specification.
    Release Candidate  

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
    Escaping (Yes) 38 (38) (Yes) (Yes) (Yes)
    Generic function ? 39 (39) ? ? ?
    Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)
    Escaping (Yes) (Yes) 38.0 (38) (Yes) (Yes) (Yes)
    Generic function ? ? 39.0 (39) ? ? ?

    See also

    Document Tags and Contributors

    Contributors to this page: evilpie, Sheppy, fscholz, Mingun, Sevenspade, arai, Mgjbot, Maian, Dria
    Last updated by: arai,