16 Sep
2011
16 Sep
'11
4:13 p.m.
Two precautions: 1. "ghc-pkg check" is incomplete: It ignores shadowing problems, which are like 99% of the problems in practice. Skip "ghc-pkg check", go straight to "ghc -v" for the real report card. 2. "ghc-pkg unregister" has a long-standing bug. I have filed it as http://hackage.haskell.org/trac/ghc/ticket/5442 In practice, 99% of the time you use "--user", so the message for you is that before you order "ghc-pkg unregister --user blah", make sure you have a "blah" in the user database. Every time. (In particular, I have seen someone ordering the same "--user" command twice for no good reason, and the first time succeeded, and therefore the second time happily went ahead to mess with the global database.)