symantic/Language/Symantic/Interpreting/Host.hs

   1 -- | Interpreter to compute a host-term.
   2 module Language.Symantic.Interpreting.Host where
   3
   4 import Control.Monad
   5
   6 -- * Type 'HostI'
   7
   8 -- | Interpreter's data.
   9 newtype HostI h = HostI { unHostI :: h }
  10 instance Functor HostI where
  11         fmap f (HostI a) = HostI (f a)
  12 instance Applicative HostI where
  13         pure = HostI
  14         (HostI f) <*> (HostI a) = HostI (f a)
  15 instance Monad HostI where
  16         return = HostI
  17         (HostI a) >>= f = f a
  18
  19 -- | Interpreter.
  20 host_from_term :: HostI h -> h
  21 host_from_term = unHostI
  22
  23 hostI0 :: a -> HostI a
  24 hostI0 = HostI
  25
  26 hostI1 :: (a -> b) -> HostI a -> HostI b
  27 hostI1 = liftM
  28
  29 hostI2 :: (a -> b -> c) -> HostI a -> HostI b -> HostI c
  30 hostI2 = liftM2
  31
  32 hostI3 :: (a -> b -> c -> d) -> HostI a -> HostI b -> HostI c -> HostI d
  33 hostI3 = liftM3