Web/JavaScript/Reference/Global objects/String/matchAll

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The matchAll() method returns an iterator of all results matching a string against a regular expression, including capturing groups.


Syntax

str.matchAll(regexp)

Parameters

regexp

A regular expression object.

If a non-RegExp object obj is passed, it is implicitly converted to a RegExp by using new RegExp(obj).

The RegExp object must have the /g flag, otherwise a TypeError will be thrown.

Return value

An iterator (which is not a restartable iterable).

Examples

Regexp.exec() and matchAll()

Prior to the addition of matchAll to JavaScript, it was possible to use calls to regexp.exec (and regexes with the /g flag) in a loop to obtain all the matches:

const regexp = RegExp('foo[a-z]*','g');
const str = 'table football, foosball';
let match;

while ((match = regexp.exec(str)) !== null) {
  console.log(`Found ${match[0]} start=${match.index} end=${regexp.lastIndex}.`);
  // expected output: "Found football start=6 end=14."
  // expected output: "Found foosball start=16 end=24."
}

With matchAll available, you can avoid the while loop and exec with g.

Instead, by using matchAll, you get an iterator to use with the more convenient for...of, array spread, or Array.from() constructs:

const regexp = RegExp('foo[a-z]*','g');
const str = 'table football, foosball';
const matches = str.matchAll(regexp);

for (const match of matches) {
  console.log(`Found ${match[0]} start=${match.index} end=${match.index + match[0].length}.`);
}
// expected output: "Found football start=6 end=14."
// expected output: "Found foosball start=16 end=24."

// matches iterator is exhausted after the for..of iteration
// Call matchAll again to create a new iterator
Array.from(str.matchAll(regexp), m => m[0]);
// Array [ "football", "foosball" ]

matchAll will throw an exception if the g flag is missing.

const regexp = RegExp('[a-c]','');
const str = 'abc';
str.matchAll(regexp);
// TypeError

matchAll internally makes a clone of the regexp—so, unlike regexp.exec(), lastIndex does not change as the string is scanned.

const regexp = RegExp('[a-c]','g');
regexp.lastIndex = 1;
const str = 'abc';
Array.from(str.matchAll(regexp), m => `${regexp.lastIndex} ${m[0]}`);
// Array [ "1 b", "1 c" ]

Better access to capturing groups (than String.prototype.match())

Another compelling reason for matchAll is the improved access to capture groups.

Capture groups are ignored when using match() with the global /g flag:

let regexp = /t(e)(st(\d?))/g;
let str = 'test1test2';

str.match(regexp);
// Array ['test1', 'test2']

Using matchAll, you can access capture groups easily:

let array = [...str.matchAll(regexp)];

array[0];
// ['test1', 'e', 'st1', '1', index: 0, input: 'test1test2', length: 4]
array[1];
// ['test2', 'e', 'st2', '2', index: 5, input: 'test1test2', length: 4]

Specifications

Specification
ECMAScript (ECMA-262)The definition of 'String.prototype.matchAll' in that specification.

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

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
matchAll Chrome

Full support 73

Edge

Full support 79

Firefox

Full support 67

IE

No support No

Opera

Full support 60

Safari

Full support 13

WebView Android

Full support 73

Chrome Android

Full support 73

Firefox Android

Full support 67

Opera Android

Full support 52

Safari iOS

Full support 13

Samsung Internet Android

No support No

nodejs

Full support 12.0.0

Legend

Full support  
Full support
No support  
No support


See also