full module names of names not in scope have gone missing in ghci

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rwbarton@morphism:/tmp$ ghci-7.10.1
GHCi, version 7.10.1: http://www.haskell.org/ghc/  :? for help
Prelude> :t GHC.Read.readPrec
GHC.Read.readPrec
  :: Read a => Text.ParserCombinators.ReadPrec.ReadPrec a

with

rwbarton@morphism:/tmp$ ~/ghc/inplace/bin/ghc-stage2 --interactive
GHCi, version 7.11.20150624: http://www.haskell.org/ghc/  :? for help
Prelude> :t GHC.Read.readPrec
GHC.Read.readPrec :: Read a => ReadPrec a

The Text.ParserCombinators.ReadPrec. bit can be quite helpful, was it suppressed intentionally?

Trac metadata

Trac field	Value
Version	7.11
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	GHCi
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	hvr
Operating system
Architecture

changed weight to 5

added GHCi Tbug Trac import labels

assigned to @simonpj

This was done purposely, but it does seem like the case here was an unintended consequence. The relevant code is (noting that ParserCombinators is from base):

  qual_name mod occ
        | [] <- unqual_gres
        , modulePackageKey mod `elem` [primPackageKey, basePackageKey, thPackageKey]
        , not (isDerivedOccName occ)
        = NameUnqual   -- For names from ubiquitous packages that come with GHC, if
                       -- there are no entities called unqualified 'occ', then
                       -- print unqualified.  Doing so does not cause ambiguity,
                       -- and it reduces the amount of qualification in error
                       -- messages.  We can't do this for all packages, because we
                       -- might get errors like "Can't unify T with T".  But the
                       -- ubiquitous packages don't contain any such gratuitous
                       -- name clashes.
                       --
                       -- A motivating example is 'Constraint'. It's often not in
                       -- scope, but printing GHC.Prim.Constraint seems overkill.

from

commit 547c597112954353cef7157cb0a389bc4f6303eb
Author:	Simon Peyton Jones <simonpj@microsoft.com>  Tue Apr  7 05:48:30 2015
Committer:	Simon Peyton Jones <simonpj@microsoft.com>  Tue Apr  7 07:10:22 2015

Reduce module qualifiers in pretty-printing

Correct. I'm not sure what the "right" solution is here. Printing qualifiers on everything in base is painful. But not printing them is also painful. Any suggestions?

closed

Fixed in #11208 (closed).

Trac metadata

Trac field	Value
Resolution	Unresolved → ResolvedDuplicate
Related	- → #11208 (closed)

changed milestone to %8.0.1

added Pnormal label