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    Length: 1887 (0x75f)
    Types: TextFile
    Names: »B«

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

TextFile

with Expression;
with More_Statements;
with Object;
with Scanner;

package body Statements is

    type Node_Structure is
        record
            Rule : Natural range 0 .. 2 := 0;
            Expr : Expression.Node := Expression.Empty_Node;
            More : More_Statements.Node := More_Statements.Empty_Node;
        end record;

    procedure Parse (N : in out Node; Error : out Boolean) is
        Failed : Boolean := False;
    begin
        if Expression.Is_First (Scanner.Get_Token) then
            N := new Node_Structure;
            N.Rule := 1;
            Expression.Parse (N.Expr, Failed);
            if not Failed then
                More_Statements.Parse (N.More, Failed);
            end if;
        else
            case Scanner.Get_Token is
                when Scanner.L_Renv =>
                    N := new Node_Structure;
                    N.Rule := 2;
                    Scanner.Next_Token;
                    Expression.Parse (N.Expr, Failed);
                when others =>
                    null;
            end case;
        end if;
        Error := Failed;
    end Parse;

    function Is_First (T : Scanner.Token) return Boolean is
        use Scanner;
    begin
        return T = Scanner.L_Renv or else Expression.Is_First (T);
    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 Statements;