String.prototype.matchAll()
BaselineWidely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.
ThematchAll()
method ofString
values returns an iterator of all results matching this string against aregular expression, includingcapturing groups.
Try it
const regexp = /t(e)(st(\d?))/g;const str = "test1test2";const array = [...str.matchAll(regexp)];console.log(array[0]);// Expected output: Array ["test1", "e", "st1", "1"]console.log(array[1]);// Expected output: Array ["test2", "e", "st2", "2"]
Syntax
matchAll(regexp)
Parameters
regexp
A regular expression object, or any object that has a
Symbol.matchAll
method.If
regexp
is not aRegExp
object and does not have aSymbol.matchAll
method, it is implicitly converted to aRegExp
by usingnew RegExp(regexp, 'g')
.If
regexp
is a regex, then it must have the global (g
) flag set, or aTypeError
is thrown.
Return value
Aniterable iterator object (which is not restartable) of matches or an empty iterator if no matches are found. Each value yielded by the iterator is an array with the same shape as the return value ofRegExp.prototype.exec()
.
Exceptions
TypeError
Thrown if the
regexp
is a regex that does not have the global (g
) flag set (itsflags
property does not contain"g"
).
Description
The implementation ofString.prototype.matchAll
doesn't do much other than calling theSymbol.matchAll
method of the argument with the string as the first parameter (apart from the extra input validation that the regex is global). The actual implementation comes fromRegExp.prototype[Symbol.matchAll]()
.
Examples
Regexp.prototype.exec() and matchAll()
WithoutmatchAll()
, it's possible to use calls toregexp.exec()
(and regexes with theg
flag) in a loop to obtain all the matches:
const 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}.`, );}// Found football start=6 end=14.// Found foosball start=16 end=24.
WithmatchAll()
available, you can avoid thewhile
loop andexec
withg
. Instead, you get an iterator to use with the more convenientfor...of
,array spreading, orArray.from()
constructs:
const 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=${ match.index + match[0].length }.`, );}// Found football start=6 end=14.// Found foosball start=16 end=24.// matches iterator is exhausted after the for...of iteration// Call matchAll again to create a new iteratorArray.from(str.matchAll(regexp), (m) => m[0]);// [ "football", "foosball" ]
matchAll
will throw an exception if theg
flag is missing.
const regexp = /[a-c]/;const str = "abc";str.matchAll(regexp);// TypeError
matchAll
internally makes a clone of theregexp
— so, unlikeregexp.exec()
,lastIndex
does not change as the string is scanned.
const regexp = /[a-c]/g;regexp.lastIndex = 1;const str = "abc";Array.from(str.matchAll(regexp), (m) => `${regexp.lastIndex} ${m[0]}`);// [ "1 b", "1 c" ]
However, this means that unlike usingregexp.exec()
in a loop, you can't mutatelastIndex
to make the regex advance or rewind.
Better access to capturing groups (than String.prototype.match())
Another compelling reason formatchAll
is the improved access to capture groups.
Capture groups are ignored when usingmatch()
with the globalg
flag:
const regexp = /t(e)(st(\d?))/g;const str = "test1test2";str.match(regexp); // ['test1', 'test2']
UsingmatchAll
, you can access capture groups easily:
const 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]
Using matchAll() with a non-RegExp implementing[Symbol.matchAll]()
If an object has aSymbol.matchAll
method, it can be used as a custom matcher. The return value ofSymbol.matchAll
becomes the return value ofmatchAll()
.
const str = "Hmm, this is interesting.";str.matchAll({ [Symbol.matchAll](str) { return [["Yes, it's interesting."]]; },}); // returns [["Yes, it's interesting."]]
Specifications
Specification |
---|
ECMAScript® 2026 Language Specification # sec-string.prototype.matchall |