src/Types/Types.hs · elk

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elk/src/Types/Types.hs

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2module Types where

4import Data.List (intercalate)

5import qualified Data.Set as Set

7type X = Int

9data Type = IntT

10 | StringT

11 | CharT

12 | BoolT

13 | LambdaT Type Type

14 | VarT X

15 | ADT String [Type]

16 deriving (Eq, Ord)

18data Scheme = Forall (Set.Set X) Type deriving (Eq, Ord, Show)

20element = ADT "Element" []

21direction = ADT "Direction" []

22text = ADT "Text" []

23listOf t = ADT "List" [t]

24tupleOf ts = ADT ("Tuple" ++ show (length ts)) ts

25string = listOf CharT

27infixr ==>

28t1 ==> t2 = LambdaT t1 t2

30infix 8 -:

31name -: tipe = (,) name tipe

33hasType t = map (-: t)

35parens = ("("++) . (++")")

37instance Show Type where

38 show t =

39 case t of

40 { IntT -> "Int"

41 ; StringT -> "String"

42 ; CharT -> "Char"

43 ; BoolT -> "Bool"

44 ; LambdaT t1@(LambdaT _ _) t2 -> parens (show t1) ++ " -> " ++ show t2

45 ; LambdaT t1 t2 -> show t1 ++ " -> " ++ show t2

46 ; VarT x -> show x

47 ; ADT "List" [tipe] -> "[" ++ show tipe ++ "]"

48 ; ADT name [] -> name

49 ; ADT name cs -> parens $ name ++ " " ++ unwords (map show cs)

50 }