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| author | Alfredo Di Napoli <alfredo@well-typed.com> | 2021-09-22 09:05:41 +0200 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2021-10-05 14:34:04 -0400 |
| commit | f52df067d288a023c52c4387841fe12a37bd1263 (patch) | |
| tree | df064b1a5b13277747c0c135a1a2966e839f4aa3 /compiler/GHC/Tc | |
| parent | 5282eaa17f976edc5bb2e43127fa40ab413a1441 (diff) | |
| download | haskell-f52df067d288a023c52c4387841fe12a37bd1263.tar.gz | |
Make GHC.Utils.Error.Validity type polymorphic
This commit makes the `Validity` type polymorphic:
```
data Validity' a
= IsValid -- ^ Everything is fine
| NotValid a -- ^ A problem, and some indication of why
-- | Monomorphic version of @Validity'@ specialised for 'SDoc's.
type Validity = Validity' SDoc
```
The type has been (provisionally) renamed to Validity' to not break
existing code, as the monomorphic `Validity` type is quite pervasive
in a lot of signatures in GHC.
Why having a polymorphic Validity? Because it carries the evidence of
"what went wrong", but the old type carried an `SDoc`, which clashed
with the new GHC diagnostic infrastructure (#18516). Having it
polymorphic it means we can carry an arbitrary, richer diagnostic type,
and this is very important for things like the
`checkOriginativeSideConditions` function, which needs to report the
actual diagnostic error back to `GHC.Tc.Deriv`.
It also generalises Validity-related functions to be polymorphic in @a@.
Diffstat (limited to 'compiler/GHC/Tc')
| -rw-r--r-- | compiler/GHC/Tc/Deriv/Generics.hs | 2 | ||||
| -rw-r--r-- | compiler/GHC/Tc/Instance/FunDeps.hs | 2 | ||||
| -rw-r--r-- | compiler/GHC/Tc/Utils/TcType.hs | 2 |
3 files changed, 3 insertions, 3 deletions
diff --git a/compiler/GHC/Tc/Deriv/Generics.hs b/compiler/GHC/Tc/Deriv/Generics.hs index 4aeac0ceae..4ad9c8b849 100644 --- a/compiler/GHC/Tc/Deriv/Generics.hs +++ b/compiler/GHC/Tc/Deriv/Generics.hs @@ -47,7 +47,7 @@ import GHC.Builtin.Names import GHC.Tc.Utils.Env import GHC.Tc.Utils.Monad import GHC.Driver.Session -import GHC.Utils.Error( Validity(..), andValid ) +import GHC.Utils.Error( Validity'(..), Validity, andValid ) import GHC.Types.SrcLoc import GHC.Data.Bag import GHC.Types.Var.Env diff --git a/compiler/GHC/Tc/Instance/FunDeps.hs b/compiler/GHC/Tc/Instance/FunDeps.hs index 8a54e03b7e..9abfc31f0b 100644 --- a/compiler/GHC/Tc/Instance/FunDeps.hs +++ b/compiler/GHC/Tc/Instance/FunDeps.hs @@ -40,7 +40,7 @@ import GHC.Types.SrcLoc import GHC.Utils.Outputable import GHC.Utils.FV -import GHC.Utils.Error( Validity(..), allValid ) +import GHC.Utils.Error( Validity'(..), Validity, allValid ) import GHC.Utils.Misc import GHC.Utils.Panic diff --git a/compiler/GHC/Tc/Utils/TcType.hs b/compiler/GHC/Tc/Utils/TcType.hs index d878ccc75a..5313ef39d4 100644 --- a/compiler/GHC/Tc/Utils/TcType.hs +++ b/compiler/GHC/Tc/Utils/TcType.hs @@ -228,7 +228,7 @@ import GHC.Data.List.SetOps ( getNth, findDupsEq ) import GHC.Utils.Outputable import GHC.Utils.Panic import GHC.Utils.Panic.Plain -import GHC.Utils.Error( Validity(..), isValid ) +import GHC.Utils.Error( Validity'(..), Validity, isValid ) import qualified GHC.LanguageExtensions as LangExt import Data.List ( mapAccumL ) |