• Ryan Scott's avatar
    Don't apply dataToTag's caseRules for data families · d8a0e6d3
    Ryan Scott authored
    Commit 193664d4 added a
    special caseRule for `dataToTag`, but this transformation completely
    broke when `dataToTag` was applied to somewith with a type headed by
    a data family, leading to #14680. For now at least, the simplest
    solution is to simply not apply this transformation when the type is
    headed by a data family.
    Test Plan: make test TEST=T14680
    Reviewers: simonpj, bgamari
    Reviewed By: bgamari
    Subscribers: rwbarton, thomie, carter
    GHC Trac Issues: #14680
    Differential Revision: https://phabricator.haskell.org/D4371
PrelRules.hs 64.1 KB