• niteria's avatar
    Use a correct substitution in tcCheckPatSynDecl · 07ed2413
    niteria authored
    The `substTheta` call didn't have the free variables of the
    `prov_theta` in the `in_scope` set. It should be enough to add
    `univ_tvs`, as all the `ex_tvs` are already in the domain of
    the substitution.
    Test Plan: added a testcase
    Reviewers: simonpj, bgamari, goldfire, austin
    Reviewed By: simonpj, bgamari
    Subscribers: thomie
    Differential Revision: https://phabricator.haskell.org/D1879
    GHC Trac Issues: #11524
TcPatSyn.hs 36.7 KB