On that note, I recently discovered that some regex engines treat some meta characters differently depending on the locale. With Python (and it changed between 2 and 3!) \w is either equivalent to [a-zA-Z0-9_], or the same one plus all the diacritics of the language (e.g. éèàùç...) (in Python, that's where the re.ASCII flags is useful
I'm curious to see how people use regexes e.g. which one do you use between \d vs [0-9], things like that?
Well 90% of my regex use is searching through codebase or logfiles or the like. Not as part of the application, so I just use whatever works. For real text, I think you'd need \p{L} (src) but unicode is tricky...