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    Length: 2350 (0x92e)
    Types: TextFile
    Names: »B«

└─⟦2f6cfab89⟧ Bits:30000547 8mm tape, Rational 1000, !projects 94-01-04
    └─⟦d65440be7⟧ »DATA« 
        └─⟦this⟧ 

TextFile

with More_List_1;
with More_List_2;
with Object;
with Scanner;

package body List is

    type Node_Structure is
        record
            Rule : Natural range 1 .. 2;
            Ident : Scanner.Lexeme := Scanner.Empty_Lexeme;
            case Rule is
                when 1 =>
                    More_1 : More_List_1.Node := More_List_1.Empty_Node;
                when 2 =>
                    Keyw : Scanner.Lexeme := Scanner.Empty_Lexeme;
                    More_2 : More_List_2.Node := More_List_2.Empty_Node;
            end case;
        end record;

    procedure Parse (N : in out Node; Error : out Boolean) is
        Failed : Boolean := False;
    begin
        case Scanner.Get_Token is
            when Scanner.L_Id =>
                N := new Node_Structure;
                N.Rule := 1;
                N.Ident := Scanner.Get_Value;
                Scanner.Next_Token;
                More_List_1.Parse (N.More_1, Failed);
            when Scanner.L_Keyw =>
                N := new Node_Structure;
                N.Rule := 2;
                N.Keyw := Scanner.Get_Value;
                Scanner.Next_Token;
                case Scanner.Get_Token is
                    when Scanner.L_Id =>
                        N.Ident := Scanner.Get_Value;
                        Scanner.Next_Token;
                        More_List_2.Parse (N.More_2, Failed);
                    when others =>
                        Failed := True;
                end case;
            when others =>
                Failed := True;
        end case;
        Error := Failed;
    end Parse;

    function Is_First (T : Scanner.Token) return Boolean is
        use Scanner;
    begin
        return T = Scanner.L_Id or else T = Scanner.L_Keyw;
    end Is_First;

    function Interpret (N : Node;
                        Inherited : Object.Reference := Object.Void_Reference)
                       return Object.Reference is
        Result : Object.Reference;
    begin
        case N.Rule is
            when 0 =>
                Result := Inherited;
            when 1 =>
                Result := Expression.Interpret (N.Expr);
                Result := More_Statements.Interpret (N.More, Result);
            when 2 =>
                Result := Expression.Interpret (N.Expr);
        end case;
        return Result;
    end Interpret;

end List;