RegEx for match/replacing JavaScript comments (both multiline and inline)

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NOTE: Regex is not a lexer or a parser. If you have some weird edge case where you need some oddly nested comments parsed out of a string, use a parser. For the other 98% of the time this regex should work.

I had pretty complex block comments going on with nested asterisks, slashes, etc. The regular expression at the following site worked like a charm:

http://upshots.org/javascript/javascript-regexp-to-remove-comments
(see below for original)

Some modifications have been made, but the integrity of the original regex has been preserved. In order to allow certain double-slash (//) sequences (such as URLs), you must use back reference $1 in your replacement value instead of an empty string. Here it is:

/\/\*[\s\S]*?\*\/|([^\\:]|^)\/\/.*$/gm

// JavaScript: 
// source_string.replace(/\/\*[\s\S]*?\*\/|([^\\:]|^)\/\/.*$/gm, '$1');

// PHP:
// preg_replace("/\/\*[\s\S]*?\*\/|([^\\:]|^)\/\/.*$/m", "$1", $source_string);

DEMO: https://regex101.com/r/B8WkuX/1

FAILING USE CASES: There are a few edge cases where this regex fails. An ongoing list of those cases is documented in this public gist. Please update the gist if you can find other cases.

…and if you also want to remove <!-- html comments --> use this:

/\/\*[\s\S]*?\*\/|([^\\:]|^)\/\/.*|<!--[\s\S]*?-->$/

(original – for historical reference only)

// DO NOT USE THIS - SEE ABOVE
/(\/\*([\s\S]*?)\*\/)|(\/\/(.*)$)/gm

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