Question

Please have a look at the REPL session below. The only difference between both regexes is order of characters in square brackets. Thus, both should yield the same output. For some reason second regex omits first sequence (123). What’s happening here? 🙂

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scala> """[^+-.,><\[\]]+""".r.findAllIn("123]asdf") foreach { println }
123
asdf

scala> """[^+-><\[\].,]+""".r.findAllIn("123]asdf") foreach { println }
asdf

Answer 1

- inside square brackets should be escaped as well. It’s used to specify ranges like [0-9] to match all digits, for example.