Web/JavaScript/Reference/Global objects/uneval

Non-standard This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

Obsolete since Gecko 74 (Firefox 74 / Thunderbird 74 / SeaMonkey 2.71)This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

The uneval() function creates a string representation of the source code of an Object.

Syntax

uneval(object)

Parameters

object: A JavaScript expression or statement.

Return value

A string representing the source code of object.

Note: This will not return a JSON representation of object.

Description

uneval() is a top-level function and is not associated with any object.

Examples

Using uneval

var a = 1;
uneval(a); // returns a String containing 1

var b = '1';
uneval(b); // returns a String containing "1"

uneval(function foo() {}); // returns "(function foo(){})"


var a = uneval(function foo() { return 'hi'; });
var foo = eval(a);
foo(); // returns "hi"

Specifications

Not part of any standard.

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
`uneval()` Deprecated'Non-standard'	Chrome No support No	Edge No support No	Firefox No support 1 — 74 Notes' No support 1 — 74 Notes' Notes' Starting in Firefox 74, `uneval()` is no longer available for use by web content. It is still allowed for internal and privileged code.	IE No support No	Opera No support No	Safari No support No	WebView Android No support No	Chrome Android No support No	Firefox Android Full support 4	Opera Android No support No	Safari iOS No support No	Samsung Internet Android No support No	nodejs No support No

Legend

Full support: Full support
No support: No support
Non-standard. Expect poor cross-browser support.': Non-standard. Expect poor cross-browser support.
Deprecated. Not for use in new websites.': Deprecated. Not for use in new websites.
See implementation notes.': See implementation notes.