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Discussion on: TIL: JavaScript replace() command with callback

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Replies for: Your code is not completely correct. The index variable in the callback is actually the position of the match in the string. So if the task is stil...

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Huy Tr. •

Yeah, that's what I noticed after posted it here, to actually replace the nth match, we can write something like this:

const replaceNth = (input, search, replacement, nth) => {
    let occurrence = 0;
    return input.replace(search, matched => {
        occurrence++;
        if (occurrence === nth) return replacement;
        return matched;
    });
};