src/Types/Types.hs · elk

on 5ba2f27 help sign in

elk/src/Types/Types.hs

38 lines 956 B history raw

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 | AppT String [Type]

16 | ADT String [Type]

17 deriving (Eq, Ord)

19data Scheme = Forall (Set.Set X) Type deriving (Eq, Ord, Show)

21data Constructor = Constructor String [Type] deriving (Eq, Show)

23parens = ("("++) . (++")")

25instance Show Type where

26 show t =

27 case t of

28 { IntT -> "Int"

29 ; StringT -> "String"

30 ; CharT -> "Char"

31 ; BoolT -> "Bool"

32 ; LambdaT t1 t2 -> parens $ show t1 ++ " -> " ++ show t2

33 ; VarT x -> show x

34 ; AppT name args -> name ++ " " ++ unwords (map show args)

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

36 ; ADT name [] -> name

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

38 }