Idris-dev/test/unique001/unique001c.idr
Edwin Brady d1941f50d3 Fix bug with Type*/AnyType in data decls
(Type* now deprecated and replaced with AnyType). If an AnyType is a
parameter of a type, the type itself must be an AnyType otherwise we
might be able to duplicate a unique thing by mistake.
2015-04-26 14:41:55 +02:00

51 lines
1.2 KiB
Idris

data UList : Type -> UniqueType where
UNil : UList a
UCons : {a : Type} -> a -> UList a -> UList a
uapp : UList a -> UList a -> UList a
uapp UNil xs = xs
uapp (UCons x xs) ys = UCons x (UCons x (uapp xs ys))
data UTree : UniqueType where
ULeaf : UTree
UNode : UTree -> Int -> UTree -> UTree
dup : UTree -> UPair UTree UTree
dup ULeaf = (ULeaf, ULeaf)
dup (UNode l y r) = let (l1, l2) = dup l
(r1, r2) = dup r in
(UNode l1 y r1, UNode l2 y r2)
data Tree : Type where
Leaf : Tree
Node : Tree -> Int -> Tree -> Tree
share : UTree -> Tree
share ULeaf = Leaf
share (UNode x y z) = Node (share x) y (share z)
class UFunctor (f : Type -> AnyType) where
fmap : (a -> b) -> f a -> f b
instance UFunctor List where
fmap f [] = []
fmap f (x :: xs) = f x :: fmap f xs
instance UFunctor UList where
fmap f UNil = UNil
fmap f (UCons x xs) = UCons (f x) (fmap f xs)
uconst : {a : AnyType} -> a -> b -> a
uconst x y = x
data MPair : AnyType -> AnyType -> AnyType where
MkMPair : {a, b : Type*} -> a -> b -> MPair a b
ndup : {a : UniqueType} -> a -> UPair a a
ndup {a} x = (\f : Int -> a => MkUPair (f 0) (f 1)) (uconst x)