Disallow class instances for synonyms
authorSimon Peyton Jones <simonpj@microsoft.com>
Tue, 21 Feb 2017 15:00:03 +0000 (15:00 +0000)
committerSimon Peyton Jones <simonpj@microsoft.com>
Tue, 21 Feb 2017 15:54:29 +0000 (15:54 +0000)
commitc7508083388a71d76a5b6f1e46adfbcffba74b96
treedd86bb37abea5c55d483f662be8ad79a23a193d0
parente3e218e2785400efb824f6652f8927690adebd20
Disallow class instances for synonyms

See Trac #13267 and Note [Instances and constraint synonyms]
in TcValidity.

We can't easily do a perfect job, because the rename is really trying
to do its lookup too early.  But this is at least an improvement.
compiler/typecheck/TcValidity.hs
testsuite/tests/polykinds/T13267.hs [new file with mode: 0644]
testsuite/tests/polykinds/T13267.stderr [new file with mode: 0644]
testsuite/tests/polykinds/all.T