da03b64 · type-level-sets

git.iko.soy/type-level-sets

change the modularisation for nub; better documentatioN

commitda03b6405ba7567b6eeb68a75e8aaa43a98c417c authorDominic Orchard <dom.orchard@gmail.com> dateThu 11 Sep 2014, 15:18 (12 years ago) parent0466aa7

3 files changed+10−10

compare with master

unifiedsplit

README+1−1 example.hs+5−7 src/Data/Type/Set.hs+4−2

README+1−1

@@ -3,7 +3,7 @@ subsets, and split sets. Also included is a "mapping" type constructor that pair

33sets of variable-type pairs, which is used in the paper "Embedding effect systems in Haskell" (Dominic Orchard,

44Tomas Petricek <http://www.cl.cam.ac.uk/~dao29/publ/haskell14-effects.pdf>) to embed effect sets.

6−A full example can be seen in 'example.hs'. Here is a shorter version:

6+The following shows an example:

88 {-# LANGUAGE DataKinds, TypeOperators #-}

example.hs+5−7

@@ -1,20 +1,18 @@

1−{-# LANGUAGE DataKinds, TypeOperators, FlexibleInstances, FlexibleContexts, GADTs #-}

1+{-# LANGUAGE DataKinds, TypeOperators #-}

33import Data.Type.Set

5−instance Nubable ((v :-> a) ': s) => Nubable ((v :-> a) ': (v :-> a) ': s) where

6− nub (Ext _ (Ext x xs)) = nub (Ext x xs)

7−

8−foo :: Set '["x" :-> Integer, "z" :-> Integer, "w" :-> Integer]

5+foo :: Set '["x" :-> Int, "z" :-> Int, "w" :-> Int]

96foo = Ext ((Var :: (Var "x")) :-> 2) $

107 Ext ((Var :: (Var "z")) :-> 4) $

118 Ext ((Var :: (Var "w")) :-> 5) $

129 Empty

1310

14−bar :: Set '["y" :-> Integer, "w" :-> Integer]

11+bar :: Set '["y" :-> Int, "w" :-> Int]

1512bar = Ext ((Var :: (Var "y")) :-> 3) $

1613 Ext ((Var :: (Var "w")) :-> 1) $

1714 Empty

1815

19−foobar :: Set '["w" :-> Integer, "x" :-> Integer, "y" :-> Integer, "z" :-> Integer]

16+-- GHC can easily infer this type, so an explicit signature not necessary

17+-- foobar :: Set '["w" :-> Int, "x" :-> Int, "y" :-> Integer, "z" :-> Int]

2018foobar = foo `union` bar

src/Data/Type/Set.hs+4−2

@@ -1,7 +1,6 @@

11{-# LANGUAGE GADTs, DataKinds, KindSignatures, TypeOperators, TypeFamilies,

22 MultiParamTypeClasses, FlexibleInstances, PolyKinds, FlexibleContexts,

3− UndecidableInstances, ConstraintKinds, OverlappingInstances, ScopedTypeVariables,

4− AllowAmbiguousTypes #-}

3+ UndecidableInstances, ConstraintKinds, OverlappingInstances, ScopedTypeVariables #-}

65module Data.Type.Set (Set(..), Union, Unionable, union, quicksort, append,

76 Sort, Sortable, Append(..), Split(..), Cmp,

@@ -111,6 +110,9 @@ instance Nubable '[] where

111110instance Nubable '[e] where

112111 nub (Ext x Empty) = Ext x Empty

113112

113+instance Nubable (e ': s) => Nubable (e ': e ': s) where

114+ nub (Ext _ (Ext e s)) = nub (Ext e s)

115+

114116instance (Nub (e ': f ': s) ~ (e ': Nub (f ': s)),

115117 Nubable (f ': s)) => Nubable (e ': f ': s) where

116118 nub (Ext e (Ext f s)) = Ext e (nub (Ext f s))