git.iko.soy/rowtype-yoga/purescript-native
on 558cd4e help sign in
rowtype-yoga/purescript-native/src/Language/PureScript/Types.hs
74 lines 2.1 kB history raw
1-----------------------------------------------------------------------------
2--
3-- Module : Language.PureScript.Types
4-- Copyright : (c) Phil Freeman 2013
5-- License : MIT
6--
7-- Maintainer : Phil Freeman <paf31@cantab.net>
8-- Stability : experimental
9-- Portability :
10--
11-- |
12--
13-----------------------------------------------------------------------------
15{-# LANGUAGE DeriveDataTypeable #-}
17module Language.PureScript.Types where
19import Data.Data
20import Language.PureScript.Names
21import Language.PureScript.Unknown (Unknown(..))
23data Type
24 = TUnknown (Unknown Type)
25 | Number
26 | String
27 | Boolean
28 | Array Type
29 | Object Row
30 | Function [PolyType] Type
31 | TypeVar String
32 | TypeConstructor (Qualified ProperName)
33 | TypeApp Type Type
34 | SaturatedTypeSynonym (Qualified ProperName) [Type]
35 | ForAll String Type
36 | Skolem Int deriving (Show, Eq, Data, Typeable)
38type PolyType = Type
40data Row
41 = RUnknown (Unknown Row)
42 | RowVar String
43 | REmpty
44 | RCons String Type Row
45 | RSkolem Int deriving (Show, Eq, Data, Typeable)
47typesToRow :: [(String, Type)] -> Row
48typesToRow [] = REmpty
49typesToRow ((name, ty):tys) = RCons name ty (typesToRow tys)
51rowToList :: Row -> ([(String, Type)], Row)
52rowToList (RCons name ty row) = let (tys, rest) = rowToList row
53 in ((name, ty):tys, rest)
54rowToList r = ([], r)
56rowFromList :: ([(String, Type)], Row) -> Row
57rowFromList ([], r) = r
58rowFromList ((name, t):ts, r) = RCons name t (rowFromList (ts, r))
60isMonoType :: Type -> Bool
61isMonoType (ForAll _ _) = False
62isMonoType ty = isPolyType ty
64isPolyType :: Type -> Bool
65isPolyType (Array ty) = isMonoType ty
66isPolyType (Object ps) = all isMonoType (map snd . fst $ rowToList ps)
67isPolyType (Function args ret) = all isPolyType args && isMonoType ret
68isPolyType (TypeApp t1 t2) = isMonoType t1 && isMonoType t2
69isPolyType (SaturatedTypeSynonym _ args) = all isMonoType args
70isPolyType (ForAll idents ty) = isPolyType ty
71isPolyType _ = True
73mkForAll :: [String] -> Type -> Type
74mkForAll = flip . foldl . flip $ ForAll