[commit: ghc] wip/impredicativity: Rework some canonicalization of InstanceOf constraints (276ec46)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : wip/impredicativity
Link       : http://ghc.haskell.org/trac/ghc/changeset/276ec4628059f68891d0909b627490df751902b0/ghc

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commit 276ec4628059f68891d0909b627490df751902b0
Author: Alejandro Serrano <trupill at gmail.com>
Date:   Fri Jul 17 14:53:00 2015 +0200

    Rework some canonicalization of InstanceOf constraints
    
    - Removed <=Trivial rule
    - Added new rule which for the case of
        (forall a. Q => a) <= sigma
      where a in a variable, produces alpha ~ sigma instead
      of the default alpha <= sigma.
    - Updated design document


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276ec4628059f68891d0909b627490df751902b0
 compiler/typecheck/TcCanonical.hs | 80 +++++++++++++++++----------------------
 compiler/typecheck/TcInteract.hs  | 36 ++----------------
 docs/types/impredicativity.ltx    | 75 ++++++++++++++++++++++--------------
 3 files changed, 84 insertions(+), 107 deletions(-)

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

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 276ec4628059f68891d0909b627490df751902b0