There are numerous posts, comments, articles and so forth about when to use regex versus using a parser. The general rule is this:
If you need to do a search from a string, such as needle(s) from a hat stack, regex is probably more ideal than a parser. If you need anything more intelligent than a list of search results you probably want a full formal parser.
Most languages allow a form of nested regex that allow for increased search precision. This occurs when a method that makes use of a regex returns to a function whose argument is a matching string result, which is why regex is probably enough when the business is primitive. There is a tremendously higher cost to using a full parser, considering the lexer and tokenizer plus rules, but it’s so much more intelligent that it’s not even comparable.
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