arguments[Symbol.iterator]()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2016.

The [Symbol.iterator]() method of arguments objects implements the iterable protocol and allows arguments objects to be consumed by most syntaxes expecting iterables, such as the spread syntax and for...of loops. It returns an array iterator object that yields the value of each index in the arguments object.

The initial value of this property is the same function object as the initial value of the Array.prototype.values property (and also the same as Array.prototype[Symbol.iterator]()).

Syntax

js
arguments[Symbol.iterator]()

Parameters

None.

Return value

The same return value as Array.prototype.values(): a new iterable iterator object that yields the value of each index in the arguments object.

Examples

Iteration using for...of loop

Note that you seldom need to call this method directly. The existence of the [Symbol.iterator]() method makes arguments objects iterable, and iterating syntaxes like the for...of loop automatically call this method to obtain the iterator to loop over.

js
function f() {
  for (const letter of arguments) {
    console.log(letter);
  }
}
f("w", "y", "k", "o", "p");

Manually hand-rolling the iterator

You may still manually call the next() method of the returned iterator object to achieve maximum control over the iteration process.

js
function f() {
  const argsIter = arguments[Symbol.iterator]();
  console.log(argsIter.next().value); // w
  console.log(argsIter.next().value); // y
  console.log(argsIter.next().value); // k
  console.log(argsIter.next().value); // o
  console.log(argsIter.next().value); // p
}
f("w", "y", "k", "o", "p");

Specifications

Specification
ECMAScript® 2027 Language Specification
# sec-createunmappedargumentsobject
ECMAScript® 2027 Language Specification
# sec-createmappedargumentsobject

Browser compatibility

desktop mobile server
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Bun
Deno
Node.js
[Symbol.iterator]
Chrome – Full support
Chrome 52 (Release date: 2016-07-20)
footnote Full support
Edge – Full support
Edge 12 (Release date: 2015-07-29)
footnote Full support
Firefox – Full support
Firefox 46 (Release date: 2016-04-26)
footnote Full support
Opera – Full support
Opera 39 (Release date: 2016-08-02)
footnote Full support
Safari – Full support
Safari 9 (Release date: 2015-09-30)
footnote Full support
Chrome Android – Full support
Chrome Android 52 (Release date: 2016-07-27)
footnote Full support
Firefox for Android – Full support
Firefox for Android 46 (Release date: 2016-04-26)
footnote Full support
Opera Android – Full support
Opera Android 41 (Release date: 2016-10-25)
footnote Full support
Safari on iOS – Full support
Safari on iOS 9 (Release date: 2015-09-16)
footnote Full support
Samsung Internet – Full support
Samsung Internet 6 (Release date: 2017-08-23)
footnote Full support
WebView Android – Full support
WebView Android 52 (Release date: 2016-07-27)
footnote Full support
WebView on iOS – Full support
WebView on iOS 9 (Release date: 2015-09-16)
footnote Full support
Bun – Full support
Bun 1 (Release date: 2023-09-08)
footnote Full support
Deno – Full support
Deno 1 (Release date: 2020-05-13)
footnote Full support
Node.js – Full support
Node.js 4 (Release date: 2015-09-08)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support

See also