Symbol.matchAll

The Symbol.matchAll well-known symbol returns an iterator, that yields matches of the regular expression against a string. This function is called by the String.prototype.matchAll() method.

This Symbol is used for String.prototype.matchAll() and specifically in RegExp.prototype[@@matchAll](). The following two examples return same result:

'abc'.matchAll(/a/);

/a/[Symbol.matchAll]('abc');

This method exists for customizing match behavior within RegExp subclasses.

let re = /[0-9]+/g;
let str = '2016-01-02|2019-03-07';

const numbers = {
  *[Symbol.matchAll] (str) {
    for (const n of str.matchAll(/[0-9]+/g))
      yield n[0];
  }
};

console.log(Array.from(str.matchAll(numbers)));
//  Array ["2016", "01", "02", "2019", "03", "07"]

See String.prototype.matchAll() and RegExp.prototype[@@matchAll]() for more examples.

• Polyfill of Symbol.matchAll in core-js
• String.prototype.matchAll()
• RegExp.prototype[@@matchAll]()