#7524: Erroneous repeated kind variable in conflicting type family instance error
message
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Reporter: goldfire | Owner:
Type: bug | Status: new
Priority: normal | Component: Compiler
Version: 7.7 | Keywords:
Os: Unknown/Multiple | Architecture: Unknown/Multiple
Failure: Incorrect warning at compile-time | Blockedby:
Blocking: | Related: #7587
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Comment(by simonpj@…):
commit a98e51ecf51d1a93d48a8a10d35827edfd9d8c28
{{{
Author: Simon Peyton Jones
Date: Mon Jan 28 08:18:28 2013 +0000
More refactoring of FamInst/FamInstEnv; finally fixes Trac #7524
Quite a bit of tidying up here; the fix to #7524 is actually
only a small part.
* Be fully clear that the cab_tvs in a CoAxBranch are not
fresh. See Note [CoAxBranch type variables] in CoAxiom.
* Use CoAxBranch to replace the ATDfeault type in Class.
CoAxBranch is perfect here. This change allowed me to
delete quite a bit of boilerplate code, including the
corresponding IfaceSynType.
* Tidy up the construction of CoAxBranches, and when FamIntBranch is
freshened. The latter onw happens only in FamInst.newFamInst.
* Tidy the tyvars of a CoAxBranch when we build them, done in
FamInst.mkCoAxBranch. See Note [Tidy axioms when we build them]
in that module. This is what fixes #7524.
Much niceer now.
compiler/iface/BinIface.hs | 7 -
compiler/iface/IfaceSyn.lhs | 31 ++---
compiler/iface/MkIface.lhs | 21 +--
compiler/iface/TcIface.lhs | 29 ++---
compiler/typecheck/FamInst.lhs | 142
++++++++++++++-------
compiler/typecheck/TcGenGenerics.lhs | 9 +-
compiler/typecheck/TcInstDcls.lhs | 50 +++-----
compiler/typecheck/TcRnDriver.lhs | 4 +-
compiler/typecheck/TcTyClsDecls.lhs | 21 ++--
compiler/types/Class.lhs | 20 +---
compiler/types/CoAxiom.lhs | 31 ++++-
compiler/types/Coercion.lhs | 1 -
compiler/types/FamInstEnv.lhs | 106 +---------------
compiler/vectorise/Vectorise/Generic/PAMethods.hs | 4 +-
compiler/vectorise/Vectorise/Generic/PData.hs | 10 +-
15 files changed, 204 insertions(+), 282 deletions(-)
}}}
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Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7524#comment:2
GHC http://www.haskell.org/ghc/
The Glasgow Haskell Compiler
