Language/Symantic/Lib/Applicative.hs

   1 {-# LANGUAGE UndecidableInstances #-}
   2 {-# OPTIONS_GHC -fno-warn-orphans #-}
   3 -- | Symantic for 'Applicative'.
   4 module Language.Symantic.Lib.Applicative where
   5
   6 import Control.Applicative (Applicative)
   7 import qualified Control.Applicative as Applicative
   8 import Control.Monad (liftM, liftM2)
   9 import qualified Data.Function as Fun
  10 import Data.Proxy
  11 import Data.Type.Equality ((:~:)(Refl))
  12 import Prelude hiding (Functor(..), (<$>), Applicative(..), id, const)
  13
  14 import Language.Symantic.Parsing
  15 import Language.Symantic.Parsing.Grammar
  16 import Language.Symantic.Typing
  17 import Language.Symantic.Compiling.Term
  18 import Language.Symantic.Lib.Lambda
  19 import Language.Symantic.Lib.Functor (Sym_Functor(..), (<$>))
  20 import Language.Symantic.Interpreting
  21 import Language.Symantic.Transforming.Trans
  22
  23 -- * Class 'Sym_Applicative'
  24 class Sym_Functor term => Sym_Applicative term where
  25         pure  :: Applicative f => term a -> term (f a)
  26         (<*>) :: Applicative f => term (f (a -> b)) -> term (f a) -> term (f b)
  27
  28         default pure  :: (Trans t term, Applicative f) => t term a -> t term (f a)
  29         default (<*>) :: (Trans t term, Applicative f)
  30          => t term (f (a -> b)) -> t term (f a) -> t term (f b)
  31
  32         pure = trans_map1 pure
  33         (<*>) = trans_map2 (<*>)
  34         (*>) :: Applicative f => term (f a) -> term (f b) -> term (f b)
  35         (<*) :: Applicative f => term (f a) -> term (f b) -> term (f a)
  36         x *> y = (lam Fun.id <$ x) <*> y
  37         x <* y = (lam (lam . Fun.const) <$> x) <*> y
  38
  39 infixl 4  *>
  40 infixl 4 <*
  41 infixl 4 <*>
  42
  43 type instance Sym_of_Iface (Proxy Applicative) = Sym_Applicative
  44 type instance Consts_of_Iface (Proxy Applicative) = Proxy Applicative ': Consts_imported_by Applicative
  45 type instance Consts_imported_by Applicative = '[]
  46
  47 instance Sym_Applicative HostI where
  48         pure  = liftM Applicative.pure
  49         (<*>) = liftM2 (Applicative.<*>)
  50 instance Sym_Applicative TextI where
  51         pure  = textI1 "pure"
  52         (<*>) = textI_infix "<*>" (infixL 4)
  53         (<* ) = textI_infix "<*"  (infixL 4)
  54         ( *>) = textI_infix "*>"  (infixL 4)
  55 instance (Sym_Applicative r1, Sym_Applicative r2) => Sym_Applicative (DupI r1 r2) where
  56         pure  = dupI1 (Proxy @Sym_Applicative) pure
  57         (<*>) = dupI2 (Proxy @Sym_Applicative) (<*>)
  58
  59 instance
  60  ( Read_TypeNameR Type_Name cs rs
  61  , Inj_Const cs Applicative
  62  ) => Read_TypeNameR Type_Name cs (Proxy Applicative ': rs) where
  63         read_typenameR _cs (Type_Name "Applicative") k = k (ty @Applicative)
  64         read_typenameR _rs raw k = read_typenameR (Proxy @rs) raw k
  65 instance Show_Const cs => Show_Const (Proxy Applicative ': cs) where
  66         show_const ConstZ{} = "Applicative"
  67         show_const (ConstS c) = show_const c
  68
  69 instance Proj_ConC cs (Proxy Applicative)
  70 data instance TokenT meta (ts::[*]) (Proxy Applicative)
  71  = Token_Term_Applicative_pure  (EToken meta '[Proxy Token_Type]) (EToken meta ts)
  72  | Token_Term_Applicative_app   (EToken meta ts)
  73  | Token_Term_Applicative_tsnoc (EToken meta ts) (EToken meta ts)
  74  | Token_Term_Applicative_const (EToken meta ts) (EToken meta ts)
  75 deriving instance (Eq meta, Eq_Token meta ts) => Eq (TokenT meta ts (Proxy Applicative))
  76 deriving instance (Show meta, Show_Token meta ts) => Show (TokenT meta ts (Proxy Applicative))
  77 instance -- CompileI
  78  ( Read_TypeName Type_Name (Consts_of_Ifaces is)
  79  , Inj_Const  (Consts_of_Ifaces is) Applicative
  80  , Inj_Const  (Consts_of_Ifaces is) (->)
  81  , Proj_Con   (Consts_of_Ifaces is)
  82  , Compile is
  83  ) => CompileI is (Proxy Applicative) where
  84         compileI tok ctx k =
  85                 case tok of
  86                  Token_Term_Applicative_pure tok_ty_f tok_a ->
  87                         -- pure :: Applicative f => a -> f a
  88                         compile_type tok_ty_f $ \(ty_f::Type (Consts_of_Ifaces is) f) ->
  89                         check_kind
  90                          (At Nothing $ SKiType `SKiArrow` SKiType)
  91                          (At (Just tok_ty_f) $ kind_of ty_f) $ \Refl ->
  92                         check_con (At (Just tok_ty_f) (ty @Applicative :$ ty_f)) $ \Con ->
  93                         compileO tok_a ctx $ \ty_a (TermO a) ->
  94                         k (ty_f :$ ty_a) $ TermO $
  95                          \c -> pure (a c)
  96                  Token_Term_Applicative_app tok_fa2b ->
  97                         -- (<*>) :: Applicative f => f (a -> b) -> f a -> f b
  98                         compileO tok_fa2b ctx $ \ty_fa2b (TermO fa2b) ->
  99                         check_con1 (ty @Applicative)
 100                          (At (Just tok_fa2b) ty_fa2b) $ \Refl Con ty_fa2b_f ty_fa2b_a2b ->
 101                         check_type2 (ty @(->)) (At (Just tok_fa2b) ty_fa2b_a2b) $ \Refl ty_fa2b_a ty_fa2b_b ->
 102                         k (ty_fa2b_f :$ ty_fa2b_a ~> ty_fa2b_f :$ ty_fa2b_b) $ TermO $
 103                          \c -> lam $ \fa -> (<*>) (fa2b c) fa
 104                  Token_Term_Applicative_const tok_fa tok_fb ->
 105                         -- (<*) :: Applicative f => f a -> f b -> f a
 106                         compileO tok_fa ctx $ \ty_fa (TermO fa) ->
 107                         compileO tok_fb ctx $ \ty_fb (TermO fb) ->
 108                         check_con1 (ty @Applicative)
 109                          (At (Just tok_fa) ty_fa) $ \Refl Con ty_fa_f _ty_fa_a ->
 110                         check_type1 ty_fa_f (At (Just tok_fb) ty_fb) $ \Refl _ty_fb_b ->
 111                         k ty_fa $ TermO $
 112                          \c -> (<*) (fa c) (fb c)
 113                  Token_Term_Applicative_tsnoc tok_fa tok_fb ->
 114                         -- (*>) :: Applicative f => f a -> f b -> f b
 115                         compileO tok_fa ctx $ \ty_fa (TermO fa) ->
 116                         compileO tok_fb ctx $ \ty_fb (TermO fb) ->
 117                         check_con1 (ty @Applicative)
 118                          (At (Just tok_fa) ty_fa) $ \Refl Con ty_fa_f _ty_fa_a ->
 119                         check_type1 ty_fa_f (At (Just tok_fb) ty_fb) $ \Refl _ty_fb_b ->
 120                         k ty_fb $ TermO $
 121                          \c -> (*>) (fa c) (fb c)
 122 instance -- TokenizeT
 123  Inj_Token meta ts Applicative =>
 124  TokenizeT meta ts (Proxy Applicative) where
 125         tokenizeT _t = mempty
 126          { tokenizers_infix = tokenizeTMod []
 127                  [ tokenize1 "<*>" (infixL 4) Token_Term_Applicative_app
 128                  , tokenize2 "<*"  (infixL 4) Token_Term_Applicative_const
 129                  , tokenize2 "*>"  (infixL 4) Token_Term_Applicative_tsnoc
 130                  ]
 131          }
 132 instance Gram_Term_AtomsT meta ts (Proxy Applicative) g