Qualified names in import lists

[Niklas Broberg]

Hi all,

I have a bug report [1] for haskell-src-exts pertaining to the use of
qualified names in import specifications, e.g.

  module Main where
  import Foo (Bar.bar)

GHC apparently accepts this code, but I can find no mention of such a
feature in the GHC docs.

Personally I don't see why this should be allowed at all, as it breaks
the abstraction layer w.r.t. re-exporting names from other, possibly
internal, modules. If there's some reasonable use for it, it should at
the very least be tied to a documented and registered extension.

I've submitted a ticket for GHC [2] to either remove this feature, or
properly document it. I'd be curious to hear what the reasoning behind
it is, if any.

Cheers,

/Niklas

ps. Why is there no "GHC accepts invalid program" option for "Type of
failure"? Too few cases? I set this ticket to Other.

[1] http://trac.haskell.org/haskell-src-exts/ticket/57
[2] http://hackage.haskell.org/trac/ghc/ticket/3792