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    Length: 3767 (0xeb7)
    Types: TextFile
    Names: »B«

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

TextFile

with Args;
with Block_Class;  
with Msg_Report;
with Object;
with Scanner;
with Statements;
with Symbol_Table;
with Unparse_Report;

package body Block is

    type Node_Structure is
        record
            Info : Natural range 0 .. 1 := 0;  
            Argu : Args.Node := Args.Empty_Node;  
            Stat : Statements.Node := Statements.Empty_Node;  
            Symb : Scanner.B_String;
            Obj : Object.Reference;  
            Lign : Integer;
        end record;

    procedure Parse (N : in out Node; Error : out Boolean) is
        Failed : Boolean := False;  
        use Scanner;

    begin  
        Msg_Report.Information ("I enter in block's parse");

        N := new Node_Structure;

        N.Lign := Scanner.Line_Number;

        Symbol_Table.New_Enter (N.Symb);
        N.Obj := Block_Class.Create (N);

        Scanner.Next;
        if Args.Is_First (Scanner.Symbol) then
            Args.Parse (N.Argu, Failed);  
            N.Info := 1;
        end if;  
        if not Failed then
            if Statements.Is_First (Scanner.Symbol) then  
                Statements.Parse (N.Stat, Failed);  
                if Scanner.Symbol = L_Close_Bracket then  
                    Scanner.Next;
                    Symbol_Table.Leave;
                else
                    Failed := True;
                    Msg_Report.Syntax_Error ("} expected, incorrect");
                end if;  
            else
                Msg_Report.Syntax_Error ("statement expected, incorrect");
                Failed := True;
            end if;

        end if;
        Msg_Report.Information ("I leave block's parse with failed = " &
                                Boolean'Image (Failed));
        Error := Failed;
    end Parse;


    procedure Unparse (N : Node) is

    begin
        Unparse_Report.Write ("{");
        Unparse_Report.Tab;
        Unparse_Report.New_Line;  
        if N.Info = 1 then
            Args.Unparse (N.Argu);
            Unparse_Report.New_Line;
        end if;
        Statements.Unparse (N.Stat);  
        Unparse_Report.Write ("} ");  
        Unparse_Report.Untab;
    end Unparse;


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

    function Interpret
                (N : Node := Empty_Node;
                 Inherited : Object.Reference := Object.Void_Reference;
                 A_Keyword_Mess : Message.Selector := Message.Void_Selector;
                 A_List : Arguments.List := Arguments.Void_Arguments  
                 ) return Object.Reference is

        Result : Object.Reference;
        Current_Table : Scanner.B_String;

        use Object;

    begin

        Msg_Report.Information ("I enter in block's interpret");

        Msg_Report.Set_Line_Number (N.Lign);

        if Inherited = Object.Void_Reference then
            -- interpretation du bloc

            Result := N.Obj;
        else
            -- evaluation du bloc

            Current_Table := Symbol_Table.Current_Block;

            Symbol_Table.Enter (N.Symb);

            if N.Info = 1 then  
                Result := Args.Interpret (N.Argu,
                                          A_Keyword_Mess => A_Keyword_Mess,
                                          A_List => A_List);
            end if;

            Result := Statements.Interpret (N.Stat);

            Symbol_Table.Enter (Current_Table);
        end if;

        Msg_Report.Information ("I leave block's interpret with result :");
        Msg_Report.Continue
           ("class = " & Object.Class'Image (Object.The_Class (Result)) &
            " ident = " & Integer'Image (Object.Identificator (Result)));

        return Result;
    end Interpret;
end Block;