Every compiler and interpreter as well as all text formats like HTML, XML, JSON, etc. have a lexing pass that uses manually crafted regular expressions. Those a

Every compiler and interpreter as well as all text formats like HTML, XML, JSON, etc. have a lexing pass that uses manually crafted regular expressions. Those are real world projects. The defensible form of this argument is that one should prefer a serialization library or a properly normalized database rather than trying to "stringly type" data and then pull it out via regexes.