diff options
Diffstat (limited to 'src/Data/Array/Nested/Internal/Shape.hs')
| -rw-r--r-- | src/Data/Array/Nested/Internal/Shape.hs | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/Data/Array/Nested/Internal/Shape.hs b/src/Data/Array/Nested/Internal/Shape.hs index b7bbf4c..59f2c9a 100644 --- a/src/Data/Array/Nested/Internal/Shape.hs +++ b/src/Data/Array/Nested/Internal/Shape.hs @@ -34,6 +34,7 @@ import Data.Kind (Type, Constraint) import Data.Monoid (Sum(..)) import Data.Proxy import Data.Type.Equality +import GHC.Exts (withDict) import GHC.IsList (IsList) import GHC.IsList qualified as IsList import GHC.TypeLits @@ -558,6 +559,9 @@ class KnownShS sh where knownShS :: ShS sh instance KnownShS '[] where knownShS = ZSS instance (KnownNat n, KnownShS sh) => KnownShS (n : sh) where knownShS = natSing :$$ knownShS +withKnownShS :: forall sh r. ShS sh -> (KnownShS sh => r) -> r +withKnownShS sh = withDict @(KnownShS sh) sh + shsKnownShS :: ShS sh -> Dict KnownShS sh shsKnownShS ZSS = Dict shsKnownShS (SNat :$$ sh) | Dict <- shsKnownShS sh = Dict |