nightshade

sem.ads (2093B)

---

with Parser; use Parser;

with Ada.Containers.Indefinite_Hashed_Maps;
with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;
with Ada.Strings.Hash;

package Sem is

   type Type_Info;
   type Function_Info;

   type Type_Info_Ref is access all Type_Info;
   type Function_Info_Ref is access all Function_Info;

   type Symbol_Kind_Enum is (SYM_FUNC, SYM_VAR, SYM_LET);
   type Type_Kind_Enum is (TY_STRING, TY_INT, TY_FLOAT, TY_BOOL, TY_VOID, TY_FUNC, TY_ERROR);

   type Type_List is array (Positive range <>) of Type_Info_Ref;
   type Type_List_Ref is access all Type_List;

   type Function_Info is record
      Params      : Type_List_Ref;
      Return_Type : Type_Info_Ref;
   end record;

   type Type_Info (Kind : Type_Kind_Enum := TY_ERROR) is record
      case Kind is
         when TY_FUNC =>
            Func : Function_Info;

         when others =>
            null;
      end case;
   end record;


   --------------------------------
   -- symbol info -----------------
   -- made of kind and type info --
   --------------------------------

   type Symbol_Info is record
      Kind : Symbol_Kind_Enum;
      Typ  : Type_Info_Ref;
   end record;

   -------------------------------------
   -- hashmap of String : Symbol_Info --
   -------------------------------------

   package Symbols_Map is new
     Ada.Containers.Indefinite_Hashed_Maps
       (Key_Type        => String,
        Element_Type    => Symbol_Info, -- symbol's info
        Hash            => Ada.Strings.Hash,
        Equivalent_Keys => "=");

   -------------
   --- scope ---
   -------------

   type Scope;

   type Scope_Ref is access Scope;

   type Scope is record
      Symbols : Symbols_Map.Map;
      Parent  : Scope_Ref;
   end record;

   ---------
   -- sem --
   ---------

   type Sem is record
      Scope : Scope_Ref;
      AST   : Declaration_Vectors.Vector;
   end record;

   ----------
   -- init --
   ----------

   function Init (AST : Declaration_Vectors.Vector) return Sem;

   --------------
   -- analysis --
   --------------

   procedure Analysis (S : in out Sem);

end Sem;