[javascript] How do you access the matched groups in a JavaScript regular expression?

String#matchAll (see the Stage 3 Draft / December 7, 2018 proposal), simplifies acccess to all groups in the match object (mind that Group 0 is the whole match, while further groups correspond to the capturing groups in the pattern):

With matchAll available, you can avoid the while loop and exec with /g... Instead, by using matchAll, you get back an iterator which you can use with the more convenient for...of, array spread, or Array.from() constructs

This method yields a similar output to Regex.Matches in C#, re.finditer in Python, preg_match_all in PHP.

See a JS demo (tested in Google Chrome 73.0.3683.67 (official build), beta (64-bit)):

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var myString = "key1:value1, key2-value2!!@key3=value3";_x000D_
var matches = myString.matchAll(/(\w+)[:=-](\w+)/g);_x000D_
console.log([...matches]); // All match with capturing group values
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The console.log([...matches]) shows

enter image description here

You may also get match value or specific group values using

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let matchData = "key1:value1, key2-value2!!@key3=value3".matchAll(/(\w+)[:=-](\w+)/g)_x000D_
var matches = [...matchData]; // Note matchAll result is not re-iterable_x000D_
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console.log(Array.from(matches, m => m[0])); // All match (Group 0) values_x000D_
// => [ "key1:value1", "key2-value2", "key3=value3" ]_x000D_
console.log(Array.from(matches, m => m[1])); // All match (Group 1) values_x000D_
// => [ "key1", "key2", "key3" ]
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NOTE: See the browser compatibility details.