Remove product functor

This was long obsoleted by the polynomial functor

ma.cabal

@@ -35,7 +35,6 @@ library
                      , MA.Functors.Bag
                      , MA.Functors.MonoidValued
                      , MA.Functors.Distribution
-                     , MA.Functors.Product
                      , MA.Functors.Polynomial
                      , MA.Functors.SomeFunctor
                      , MA.Parser

src/MA/Functors/Product.hs

-module MA.Functors.Product
-  ( product
-  , Product(..)
-  ) where
-
-import           Control.Monad (void)
-import           Prelude hiding (product)
-
-import           Data.Tuple.Extra (both)
-
-import           MA.RefinementInterface
-import qualified MA.Parser.Lexer as L
-import           MA.FunctorExpression.Parser
-import           MA.Coalgebra.RefinementTypes
-import           MA.Coalgebra.Parser
-
-data Product a = Product a a
-  deriving (Show, Functor, Foldable, Traversable)
-
-product :: FunctorParser Product
-product = infixR $ do
-  void $ L.symbol "×"
-  return Product
-
-data Side = L | R
-  deriving (Eq)
-
-data Three = ToRest | ToCompound | ToSub
-  deriving (Show, Eq, Ord, Enum)
-
-type instance H1 Product = ()
-type instance H3 Product = (Three, Three)
-type instance Label Product = Side
-type instance Weight Product = (Bool, Bool)
-
-instance ParseMorphism Product where
-  parseMorphismPoint (Product parseLeft parseRight) = L.parens $ do
-    left <- parseLeft
-    void L.comma
-    right <- parseRight
-
-    return ((), [(left, L), (right, R)])
-
-instance RefinementInterface Product where
-  init :: H1 Product -> [Label Product] -> Weight Product
-  init _ _ = (True, True)
-
-  update :: [Label Product] -> Weight Product -> (Weight Product, H3 Product, Weight Product)
-  update labels (left, right) = val up
-    where
-      val h3 = (both (==ToSub) h3, h3, both (==ToCompound) h3)
-
-      up = (left +? (L `elem` labels), right +? (R `elem` labels))
-
-      (+?) :: Bool -> Bool -> Three
-      a +? b = toEnum (fromEnum a + fromEnum b)