Correct order of existentials in pattern synonyms
authorSimon Peyton Jones <simonpj@microsoft.com>
Fri, 14 Oct 2016 14:54:14 +0000 (15:54 +0100)
committerSimon Peyton Jones <simonpj@microsoft.com>
Mon, 17 Oct 2016 07:41:23 +0000 (08:41 +0100)
commita693d1cb0ee9499af3145d73b1aebe5b6df0da98
tree7b4bb2b1acbf2d5181c8811747c4f3769a18fe90
parent609d2c813b6e9cf059e88d2bc05e0295a9f56007
Correct order of existentials in pattern synonyms

Trac #12698 exposed a nasty bug in the typechecking for
pattern synonmys: the existential type variables weren't
being put in properly-scoped order.

For some reason TcPatSyn.tcCollectEx was colleting them as a
set, not as a list!  Easily fixed.
compiler/hsSyn/HsPat.hs
compiler/typecheck/TcPatSyn.hs
testsuite/tests/patsyn/should_compile/T12698.hs [new file with mode: 0644]
testsuite/tests/patsyn/should_compile/all.T