gengen/src/GenType.dcl

   1 definition module GenType
   2
   3 import StdGeneric
   4 from StdOverloaded import class ==, class toString
   5
   6 //* Auxiliary type to help with casting values, this is gone at runtime
   7 :: Box b a =: Box b
   8 derive bimap Box
   9 unBox (Box b) :== b
  10 box b :== Box b
  11 reBox x :== box (unBox x)
  12
  13 //* Deeply embedded generic type representation
  14 :: GType
  15         = GTyBasic BasicType
  16         | GTyRef String
  17         | GTyArrow GType GType
  18         | GTyArray ArrayType GType
  19         | GTyUList UListType GType
  20         | GTyUMaybe GType
  21         | GTyUnit
  22         | GTyEither GType GType
  23         | GTyPair GType GType
  24         | GTyCons GenericConsDescriptor GType
  25         | GTyField GenericFieldDescriptor GType
  26         | GTyObject GenericTypeDefDescriptor GType
  27         | GTyRecord GenericRecordDescriptor GType
  28
  29 //* Type representation larded with the generic type information
  30 :: Type
  31         = TyBasic BasicType
  32         | TyRef String
  33         | TyArrow Type Type
  34         | TyArray ArrayType Type
  35         | TyUList UListType Type
  36         | TyUMaybe Type
  37         | TyNewType GenericTypeDefDescriptor GenericConsDescriptor Type
  38         | TyObject GenericTypeDefDescriptor [(GenericConsDescriptor, [Type])]
  39         | TyRecord GenericRecordDescriptor [(GenericFieldDescriptor, Type)]
  40
  41 //* Basic types
  42 :: BasicType = BTInt | BTChar | BTReal | BTBool | BTDynamic | BTFile | BTWorld
  43 //* Array kinds
  44 :: ArrayType = AStrict | ALazy | AUnboxed | APacked
  45 //* Unboxed list kinds
  46 :: UListType = ULLazy | ULStrict
  47 //* Kind of a type
  48 :: Kind = KStar | (KArrow) infixr 1 Kind Kind
  49
  50 instance == GType, Type, BasicType, ArrayType, UListType, GenType, Kind
  51 instance toString GType, Type, BasicType, ArrayType, UListType, GenType, Kind
  52
  53 /**
  54  * Removes recursive types by replacing them with references
  55  *
  56  * @param gtype
  57  * @result the main type
  58  * @result the separated types grouped in strongly connected components
  59  */
  60 flattenGType :: GType -> [[GType]]
  61
  62 //* Convert a GType to a Type
  63 gTypeToType :: GType -> Type
  64
  65 //* Extract the name of the type
  66 typeName :: Type -> String
  67
  68 //* Extract the genType for a type
  69 typeGenType :: Type -> [GenType]
  70
  71 //* Extract the kind of the type's constructors (see `{{typeGenType}}`)
  72 genTypeKind :: [GenType] -> Kind
  73 //* @type Type -> Kind
  74 typeKind t :== genTypeKind (typeGenType t)
  75
  76 //* Predicate whether the outer type is a builtin type
  77 class isBuiltin a :: a -> Bool
  78 instance isBuiltin Type, GType
  79
  80 //* Predicate whether the outer type is a basic type
  81 class isBasic a :: a -> Bool
  82 instance isBasic Type, GType
  83
  84 //* Replace builtin constructors with their pretty names (e.g. _!Cons with [!])
  85 class replaceBuiltins a :: a -> a
  86 instance replaceBuiltins Type, GType, GenType
  87
  88 //* Creates a deep embedded generic representation of a type
  89 generic gType a :: Box GType a
  90 derive gType UNIT, EITHER, PAIR, CONS of gcd, FIELD of gfd, OBJECT of gtd, RECORD of grd
  91 derive gType Int, Bool, Real, Char, World, File
  92 derive gType (->)
  93 derive gType ?#, ?, ?^
  94 derive gType [], [! ], [ !], [!!], [#], [#!], {}, {!}, {#}, {32#}
  95 derive gType (), (,), (,,), (,,,), (,,,,), (,,,,,), (,,,,,,), (,,,,,,,)