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    Length: 1360 (0x550)
    Types: TextFile
    Names: »B«

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

TextFile

with Primary, More_Unary;

package body Unary is

    type Node_Structure is
        record
            Rule : Natural range 0 .. 1 := 0;
            Prim : Primary.Node := Primary.Empty_Node;
            More : More_Unary.Node := More_Unary.Empty_Node;
            Line : Object.Index := Scanner.Get_Line_Number;
        end record;

    procedure Parse (N : in out Node) is
        use Scanner;
    begin  
        N := new Node_Structure;
        N.Rule := 0;
        Primary.Parse (N.Prim);
        if Scanner.Get_Token = Scanner.Identifier then
            N.Rule := 1;
            More_Unary.Parse (N.More);
        end if;
    end Parse;

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

    procedure Unparse (N : Node) is
        Result : Object.Reference;
    begin
        Primary.Unparse (N.Prim);
        if N.Rule = 1 then
            More_Unary.Unparse (N.More);
        end if;
    end Unparse;

    function Interpret (N : Node) return Object.Reference is
        Result : Object.Reference;
    begin
        Scanner.Put_Line_Number (N.Line);
        Result := Primary.Interpret (N.Prim);
        if N.Rule = 1 then
            Result := More_Unary.Interpret (N.More, Result);
        end if;
        return Result;
    end Interpret;
end Unary;