+type TypeMap = Map.Map OrdType (AST.VHDLId, Either AST.TypeDef AST.SubtypeIn)
+
+-- A map of Elem types to the corresponding VHDL Id for the Vector
+type ElemTypeMap = Map.Map OrdType (AST.VHDLId, AST.TypeDef)
+
+-- A map of a vector Core element type and function name to the coressponding
+-- VHDLId of the function and the function body.
+type TypeFunMap = Map.Map (OrdType, String) (AST.VHDLId, AST.SubProgBody)