diff options
Diffstat (limited to 'compiler/GHC/Tc/Instance')
| -rw-r--r-- | compiler/GHC/Tc/Instance/Class.hs | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/compiler/GHC/Tc/Instance/Class.hs b/compiler/GHC/Tc/Instance/Class.hs index 2bac6fa3ab..0d96d4420e 100644 --- a/compiler/GHC/Tc/Instance/Class.hs +++ b/compiler/GHC/Tc/Instance/Class.hs @@ -571,15 +571,15 @@ Some further observations about `withDict`: (WD3) As an alternative to `withDict`, one could define functions like `withT` above in terms of `unsafeCoerce`. This is more error-prone, however. -(WD4) In order to define things like `reifySymbol` below: +(WD4) In order to define things like `withKnownNat` below: - reifySymbol :: forall r. String -> (forall (n :: Symbol). KnownSymbol n => r) -> r + withKnownNat :: SNat n -> (KnownNat n => r) -> r `withDict` needs to be instantiated with `Any`, like so: - reifySymbol n k = withDict @(KnownSymbol Any) @String @r n (k @Any) + withKnownNat = withDict @(KnownNat Any) @(SNat Any) @r - The use of `Any` is explained in Note [NOINLINE someNatVal] in + The use of `Any` is explained in Note [NOINLINE withSomeSNat] in base:GHC.TypeNats. (WD5) In earlier implementations, `withDict` was implemented as an identifier |