diff options
| author | Simon Peyton Jones <simonpj@microsoft.com> | 2020-10-31 08:29:08 -0400 |
|---|---|---|
| committer | Ryan Scott <ryan.gl.scott@gmail.com> | 2020-10-31 12:00:01 -0400 |
| commit | 3e070cffc16ab6817b4cb6bb64f5bedabbe51da9 (patch) | |
| tree | b2c6e075d0edd3e682cefeed7ff2a4aa78441b5e /compiler/GHC/Tc/Module.hs | |
| parent | 08e6993a1b956e6edccdc1cecc7250b724bf79a0 (diff) | |
| download | haskell-wip/T13795-T18828.tar.gz | |
Expand type synonyms with :kind!wip/T13795-T18828
The User's Guide claims that `:kind!` should expand type synonyms,
but GHCi wasn't doing this in practice. Let's just update the implementation
to match the specification in the User's Guide.
Fixes #13795. Fixes #18828.
Co-authored-by: Ryan Scott <ryan.gl.scott@gmail.com>
Diffstat (limited to 'compiler/GHC/Tc/Module.hs')
| -rw-r--r-- | compiler/GHC/Tc/Module.hs | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/compiler/GHC/Tc/Module.hs b/compiler/GHC/Tc/Module.hs index 94582b00a9..2d44a9aacf 100644 --- a/compiler/GHC/Tc/Module.hs +++ b/compiler/GHC/Tc/Module.hs @@ -2629,12 +2629,13 @@ tcRnType hsc_env flexi normalise rdr_type -- Do validity checking on type ; checkValidType (GhciCtxt True) ty - ; ty' <- if normalise - then do { fam_envs <- tcGetFamInstEnvs - ; let (_, ty') - = normaliseType fam_envs Nominal ty - ; return ty' } - else return ty ; + -- Optionally (:k vs :k!) normalise the type. Does two things: + -- normaliseType: expand type-family applications + -- expandTypeSynonyms: expand type synonyms (#18828) + ; fam_envs <- tcGetFamInstEnvs + ; let ty' | normalise = expandTypeSynonyms $ snd $ + normaliseType fam_envs Nominal ty + | otherwise = ty ; return (ty', mkInfForAllTys kvs (tcTypeKind ty')) } |