{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE NoMonomorphismRestriction #-}
module Symantic.Parser.Grammar
 ( module Symantic.Parser.Grammar
 , module Symantic.Parser.Grammar.Combinators
 , module Symantic.Parser.Grammar.Optimize
 , module Symantic.Parser.Grammar.ObserveSharing
 , module Symantic.Parser.Grammar.Write
 , module Symantic.Parser.Grammar.Dump
 ) where
import Symantic.Parser.Grammar.Combinators
import Symantic.Parser.Grammar.Optimize
import Symantic.Parser.Grammar.ObserveSharing
import Symantic.Parser.Grammar.Write
import Symantic.Parser.Grammar.Dump
import Symantic.Univariant.Letable (Letable)

import Data.Function ((.))
import Data.String (String)
import System.IO (IO)
import Text.Show (Show(..))
import qualified Data.Functor as Functor
import qualified Language.Haskell.TH.Syntax as TH

-- Class 'Grammar'
type Grammar repr =
  ( Applicable repr
  , Alternable repr
  , Charable repr
  , Letable TH.Name repr
  , Selectable repr
  , Matchable repr
  , Foldable repr
  , Lookable repr
  )

-- | A usual pipeline to show 'Comb'inators: 'observeSharing' then 'optimizeComb' then 'dumpComb' then 'show'.
-- Note that the 'IO' is required to 'observeSharing' which is required to avoid an infinite recursion when generating.
grammar = (optimizeComb Functor.<$>) . observeSharing

-- | A usual pipeline to show 'Comb'inators: 'observeSharing' then 'optimizeComb' then 'dumpComb' then 'show'.
-- Note that the 'IO' is required to 'observeSharing' which is required to avoid an infinite recursion when the grammar is recursive.
showGrammar :: ObserveSharing TH.Name (OptimizeComb TH.Name DumpComb) a -> IO String
showGrammar = (show . dumpComb . optimizeComb Functor.<$>) . observeSharing