Exposing newtype coercions to Haskell

Joachim Breitner mail at joachim-breitner.de
Wed Jul 3 12:33:11 CEST 2013


Am Dienstag, den 02.07.2013, 12:56 -0500 schrieb Nicolas Frisby:

> For my light experimentation, I have recovered these two values from
> the ModGuts that all plugins receive. Hopefully someone will shout out
> if there's pitfalls to avoid.
>   * The mg_rdr_env field is of type GlobalRdrEnv.

strange, why did I miss that?

But I can’t get it to work, even looking up an element that I took from
the GRE itself returns []:

    let e' = head (head (occEnvElts env))
    putMsgS $ showSDoc dflags (ppr e')
    putMsgS $ showSDoc dflags (ppr (lookupGRE_RdrName (nameRdrName (gre_name e')) env))

          imported from `GHC.NT.Type' at GHC/NT.hs:5:1-18
          (and originally defined at GHC/NT/Type.hs:6:6-7)
Also, trying to construct a RdrName that I can look up fails:

    let rdrName = mkRdrQual (mkModuleName "GHC.NT.Type") (mkTcOcc "NT")
    putMsgS $ showSDoc dflags (ppr (lookupGRE_RdrName rdrName env))

prints also just [].

What am I doing wrong?


Joachim “nomeata” Breitner
  mail at joachim-breitner.dehttp://www.joachim-breitner.de/
  Jabber: nomeata at joachim-breitner.de  • GPG-Key: 0x4743206C
  Debian Developer: nomeata at debian.org
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