purescript/purescript — pull request #785 by dylex (2014-12-25 19:21:06+00:00)
Title: Lift restriction on underscores in unames

Also allows apostrophes.

The only trick here is we need to keep the restriction on module names, due to CommonJS module naming. I did a quick review of the rest of the parser and didn't find anywhere else that module names were parsed as normal unames. Requested by @jutaro.