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    Length: 1520 (0x5f0)
    Types: TextFile
    Names: »B«

└─⟦a7d1ea751⟧ Bits:30000550 8mm tape, Rational 1000, !users!projects 94_04_11
    └─ ⟦129cab021⟧ »DATA« 
        └─⟦this⟧ 

TextFile

with Object, Message, Scanner, Printer;
package body More_Unary is

    type Node_Structure is
        record
            Rule : Natural range 0 .. 1 := 0;
            More : More_Unary.Node := Empty_Node;
            Mess : Message.Tiny_String;
            Line : Natural;
        end record;



    procedure Parse (N : in out Node) is
        use Scanner;
    begin  
        N := new Node_Structure;
        N.Line := Scanner.Get_Line_Number;
        N.Mess := Scanner.Get_Value;  
        Scanner.Next;
        if Is_First (Scanner.Get_Token) then
            N.Rule := 1;
            Parse (N.More);
        end if;
    end Parse;

    procedure Unparse (N : in Node) is
    begin
        Scanner.Set_Line_Number (N.Line);
        Printer.Write (N.Mess);
        if N.Rule = 1 then
            Unparse (N.More);
        end if;
    end Unparse;

    function Is_First (T : Scanner.Token) return Boolean is
        use Scanner;
    begin
        return T = T_Identifier;
    end Is_First;

    function Interpret (N : Node; Inherited : Object.Reference)
                       return Object.Reference is
        Result : Object.Reference;
    begin  
        Scanner.Set_Line_Number (N.Line);
        case N.Rule is
            when 0 =>  
                Result := Message.Send (Inherited, N.Mess);
            when 1 =>  
                Result := Message.Send (Inherited, N.Mess);
                Result := Interpret (N.More, Result);
        end case;
        return (Result);
    end Interpret;
end More_Unary;