[commit: ghc] tc-untouchables: Another refactoring of constraints (d30b9cf)

Repository : ssh://darcs.haskell.org//srv/darcs/ghc

On branch  : tc-untouchables

http://hackage.haskell.org/trac/ghc/changeset/d30b9cf45793c9e674463c86345931cbae345e7a

>---------------------------------------------------------------

commit d30b9cf45793c9e674463c86345931cbae345e7a
Author: Simon Peyton Jones <[email protected]>
Date:   Mon Sep 10 10:01:51 2012 +0100

    Another refactoring of constraints
    
    1. Rejig CtLoc
       * CtLoc is now *not* parameterised (much simpler)
       * CtLoc includes the "depth" of the constraint
       * CtLoc includes the TcLclEnv at the birthplace
         That gives (a) the SrcSpan, (b) the [ErrCtxt]
         (c) the [TcIdBinder]
       * The CtLoc of a constraint is no longer in its CtEvidence
       * Where we passed 'depth' before, now we pass CtLoc
    
    2. Some significant refactoring in TcErrors
       * Get rid of cec_extra
       * Traverse every constraint, so that we can be
         sure to generate bindings where necessary.
         (This was really a lurking bug before.)
    
    3. Merge zonking into TcCanonical.  This turned out to be
       almost trivial; just a small change to TcCanonical.flattenTyVar.
    
       The nice consequence is that we don't need to zonk a constraint
       before solving it; instead it gets zonked "on the fly" as it were.

 compiler/typecheck/Inst.lhs        |  101 ++------
 compiler/typecheck/TcCanonical.lhs |  417 ++++++++++++++---------------
 compiler/typecheck/TcErrors.lhs    |  509 +++++++++++++++---------------------
 compiler/typecheck/TcExpr.lhs      |    2 +-
 compiler/typecheck/TcInteract.lhs  |  207 +++++++--------
 compiler/typecheck/TcMType.lhs     |   26 +--
 compiler/typecheck/TcRnMonad.lhs   |    9 +-
 compiler/typecheck/TcRnTypes.lhs   |  157 +++++------
 compiler/typecheck/TcRules.lhs     |    8 +-
 compiler/typecheck/TcSMonad.lhs    |   90 ++++---
 compiler/typecheck/TcSimplify.lhs  |   28 ++-
 compiler/typecheck/TcType.lhs      |   19 +-
 compiler/typecheck/TcUnify.lhs     |    9 +-
 13 files changed, 695 insertions(+), 887 deletions(-)


Diff suppressed because of size. To see it, use:

    git show d30b9cf45793c9e674463c86345931cbae345e7a