Is there a way to know if a regex match failed because it reached the end of the string?

For example if I have the the regex /a\d+b/ that matches the string a123 the regex fails, and the regex engine inspected the end of the string. Is there a way to tell if that has happened?

I want to check this because I want to write a tokenizer that reads a file line by line, and matches user supplied regexes against the string.

Now I don't know in advance how many lines to read before trying to match, so the idea is to check whether the regex failed while being in the middle of a regex.

If there's a better solution to that I'm happy as well ;-)

In reply to Did regex match fail because of "end of string"? by moritz

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