[GHC] #15269: Qualified Names in --show-iface output

[GHC]

#15269: Qualified Names in --show-iface output
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        Reporter:  sjakobi           |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 I didn't know this, but indeed `--show-iface` doesn't seem to show
 qualified names, which is confusing in unfoldings.   (It might be
 reasonable not to quality names from the current module.)

 This is controlled by the pretty-printing style.  I'm not sure how
 `--show-iface` invokes the pretty-printer, but it looks as though
 `defaultUserStyle` omits the module qualifier on everything, which isn't
 what we want here
 {{{
 defaultUserStyle :: DynFlags -> PprStyle
 defaultUserStyle dflags = mkUserStyle dflags neverQualify AllTheWay
 }}}
 Note that `neverQualify`.

 So I think you could fix it for all of `--show-iface` not just for
 docstring.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15269#comment:4>
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