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authorTom Smeding <t.j.smeding@uu.nl>2024-04-03 12:37:35 +0200
committerTom Smeding <t.j.smeding@uu.nl>2024-04-03 12:37:35 +0200
commit92902c4f66db111b439f3b7eba9de50ad7c73f7b (patch)
tree27f12853825b7dd13d4bc8040dd2be6781deb635 /src/Nats.hs
parent264c8e601f49cebed9280f0da2e73f380bb5be52 (diff)
Reorganise, documentation
Diffstat (limited to 'src/Nats.hs')
-rw-r--r--src/Nats.hs58
1 files changed, 0 insertions, 58 deletions
diff --git a/src/Nats.hs b/src/Nats.hs
deleted file mode 100644
index fdc090e..0000000
--- a/src/Nats.hs
+++ /dev/null
@@ -1,58 +0,0 @@
-{-# LANGUAGE DataKinds #-}
-{-# LANGUAGE GADTs #-}
-{-# LANGUAGE PolyKinds #-}
-{-# LANGUAGE ScopedTypeVariables #-}
-{-# LANGUAGE StandaloneDeriving #-}
-{-# LANGUAGE TypeApplications #-}
-{-# LANGUAGE TypeFamilies #-}
-{-# LANGUAGE TypeOperators #-}
-{-# LANGUAGE UndecidableInstances #-}
-{-# OPTIONS_GHC -fplugin GHC.TypeLits.KnownNat.Solver #-}
-module Nats where
-
-import Data.Proxy
-import Numeric.Natural
-import qualified GHC.TypeLits as G
-
-
-data Dict c a where
- Dict :: c a => Dict c a
-
-data Nat = Z | S Nat
- deriving (Show)
-
-data SNat n where
- SZ :: SNat Z
- SS :: SNat n -> SNat (S n)
-deriving instance Show (SNat n)
-
-class KnownNat n where knownNat :: SNat n
-instance KnownNat Z where knownNat = SZ
-instance KnownNat n => KnownNat (S n) where knownNat = SS knownNat
-
-unSNat :: SNat n -> Natural
-unSNat SZ = 0
-unSNat (SS n) = 1 + unSNat n
-
-unNat :: Nat -> Natural
-unNat Z = 0
-unNat (S n) = 1 + unNat n
-
-snatKnown :: SNat n -> Dict KnownNat n
-snatKnown SZ = Dict
-snatKnown (SS n) | Dict <- snatKnown n = Dict
-
-type family n + m where
- Z + m = m
- S n + m = S (n + m)
-
-type family GNat n where
- GNat Z = 0
- GNat (S n) = 1 G.+ GNat n
-
-gknownNat :: KnownNat n => Proxy n -> Dict G.KnownNat (GNat n)
-gknownNat (Proxy @n) = go (knownNat @n)
- where
- go :: SNat m -> Dict G.KnownNat (GNat m)
- go SZ = Dict
- go (SS n) | Dict <- go n = Dict