[commit: ghc] master: Fix scoping of pattern-synonym existentials (f1fe5b4)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/f1fe5b4adf6a4094ecc600a28f64f7628903d017/ghc

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

commit f1fe5b4adf6a4094ecc600a28f64f7628903d017
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Dec 18 12:03:33 2017 +0000

    Fix scoping of pattern-synonym existentials
    
    This patch fixes Trac #14998, where we eventually decided that
    the existential type variables of the signature of a pattern
    synonym should not scope over the pattern synonym.
    
    See Note [Pattern synonym existentials do not scope] in TcPatSyn.


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

f1fe5b4adf6a4094ecc600a28f64f7628903d017
 compiler/basicTypes/PatSyn.hs                     |  2 +-
 compiler/typecheck/TcHsType.hs                    | 12 +--
 compiler/typecheck/TcPatSyn.hs                    | 95 +++++++++++++++++++++++
 compiler/typecheck/TcRnTypes.hs                   |  5 ++
 compiler/typecheck/TcSigs.hs                      | 43 +---------
 docs/users_guide/glasgow_exts.rst                 | 18 ++++-
 testsuite/tests/patsyn/should_fail/T11265.stderr  |  2 +-
 testsuite/tests/patsyn/should_fail/T14498.hs      | 32 ++++++++
 testsuite/tests/patsyn/should_fail/T14498.stderr  |  8 ++
 testsuite/tests/patsyn/should_fail/T9161-1.stderr |  5 +-
 testsuite/tests/patsyn/should_fail/T9161-2.stderr |  5 +-
 testsuite/tests/patsyn/should_fail/all.T          |  1 +
 testsuite/tests/polykinds/T5716.stderr            | 10 +--
 testsuite/tests/polykinds/T7433.stderr            | 10 +--
 14 files changed, 182 insertions(+), 66 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 f1fe5b4adf6a4094ecc600a28f64f7628903d017