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    1 {-# LANGUAGE DeriveGeneric, DeriveDataTypeable, DeriveFunctor, DeriveTraversable, DeriveFoldable #-}
    2 {-# LANGUAGE UndecidableInstances #-}
    3 
    4 module Conjure.Language.Expression.Op.Product where
    5 
    6 import Conjure.Prelude
    7 import Conjure.Language.Expression.Op.Internal.Common
    8 
    9 import qualified Data.Aeson as JSON             -- aeson
   10 import qualified Data.Aeson.KeyMap as KM
   11 
   12 import qualified Data.Vector as V               -- vector
   13 
   14 
   15 data OpProduct x = OpProduct x
   16     deriving (Eq, Ord, Show, Data, Functor, Traversable, Foldable, Typeable, Generic)
   17 
   18 instance Serialize x => Serialize (OpProduct x)
   19 instance Hashable  x => Hashable  (OpProduct x)
   20 instance ToJSON    x => ToJSON    (OpProduct x) where toJSON = genericToJSON jsonOptions
   21 instance FromJSON  x => FromJSON  (OpProduct x) where parseJSON = genericParseJSON jsonOptions
   22 
   23 instance (TypeOf x, Pretty x, ExpressionLike x) => TypeOf (OpProduct x) where
   24     typeOf p@(OpProduct x) = do
   25         ty <- typeOf x
   26         innerTy <- case ty of
   27             TypeList t -> return t
   28             TypeMatrix _ t -> return t
   29             TypeSet t -> return t
   30             TypeMSet t -> return t
   31             _ -> raiseTypeError $ vcat [ pretty p
   32                                        , "The argument has type:" <+> pretty ty
   33                                        ]
   34         case innerTy of
   35             TypeAny | Just [] <- listOut x -> return (TypeInt TagInt)
   36             TypeInt t | ?typeCheckerMode == RelaxedIntegerTags -> return (TypeInt t)
   37             TypeInt TagInt -> return (TypeInt TagInt)
   38             _ -> raiseTypeError $ vcat [ pretty p
   39                                        , "The argument has type:" <+> pretty ty
   40                                        ]
   41 
   42 instance BinaryOperator (OpProduct x) where
   43     opLexeme _ = L_Times
   44 
   45 instance (OpProduct x :< x) => SimplifyOp OpProduct x where
   46     simplifyOp (OpProduct x)
   47         | Just xs <- listOut x
   48         , let filtered = filter (/=0) xs
   49         , length filtered /= length xs      -- there were 0's
   50         = return 0
   51     simplifyOp (OpProduct x)
   52         | Just xs <- listOut x
   53         , let filtered = filter (/=1) xs
   54         , length filtered /= length xs      -- there were 1's
   55         = case filtered of
   56             []  -> return 1
   57             [n] -> return n
   58             _   -> return $ inject $ OpProduct $ fromList filtered
   59     simplifyOp _ = na "simplifyOp{OpProduct}"
   60 
   61 instance (Pretty x, ExpressionLike x) => Pretty (OpProduct x) where
   62     prettyPrec prec op@(OpProduct x) | Just [a,b] <- listOut x = prettyPrecBinOp prec [op] a b
   63     prettyPrec _ (OpProduct x) = "product" <> prParens (pretty x)
   64 
   65 instance (VarSymBreakingDescription x, ExpressionLike x) => VarSymBreakingDescription (OpProduct x) where
   66     varSymBreakingDescription (OpProduct x) | Just xs <- listOut x = JSON.Object $ KM.fromList
   67         [ ("type", JSON.String "OpProduct")
   68         , ("children", JSON.Array $ V.fromList $ map varSymBreakingDescription xs)
   69         , ("symmetricChildren", JSON.Bool True)
   70         ]
   71     varSymBreakingDescription (OpProduct x) = JSON.Object $ KM.fromList
   72         [ ("type", JSON.String "OpProduct")
   73         , ("children", varSymBreakingDescription x)
   74         ]