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    Types: TextFile
    Names: »B«

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

TextFile

with Stack_Generic;
with Lexical;
use Lexical;  
with Erreurs;

separate (Semantique)
package body Calcul is

    subtype Facteur is Integer;
    type Ptr_Facteur is access Facteur;

    type Operateur is ('(', '+', '-', '*', 'p', 'm', ')', Finop);
    package Es_Op is new Text_Io.Enumeration_Io (Operateur);
    use Es_Op;

    type Elt (Isfact : Boolean) is
        record
            case Isfact is
                when False =>
                    Op : Operateur;
                when True =>
                    Fact : Ptr_Facteur;
            end case;
        end record;
    type Ptr_Elt is access Elt;


    Var_Undef : exception;


    package Pilfact is new Stack_Generic (Ptr_Facteur);
    Pile : Pilfact.Stack;


    package Piloper is new Stack_Generic (Operateur);
    Pilop : Piloper.Stack;


    Par_Ferm, Err_Op : exception;
    Precoper : Boolean := True;
    Op_Inconnu : Character;


    procedure Getval (Nb : out Integer) is
        F : Ptr_Facteur;
    begin
        F := Pilfact.Top (Pile);
        Pilfact.Pop (Pile);
        Nb := F.all;
    end Getval;


    function Lirelem (Un_Token : Lexical.Token; Une_Valeur : Integer)
                     return Ptr_Elt is separate;


    procedure Demarre_Calcul is
    begin  
        Pilfact.Make_Empty (Pile);
        Piloper.Make_Empty (Pilop);
        Piloper.Push (Finop, Pilop);
    end Demarre_Calcul;


    procedure Calculateur (Un_Elem : Ptr_Elt) is separate;


    procedure Postfixer (Un_Elem : Ptr_Elt) is separate;


    procedure Empiler (Un_Jeton : Lexical.Token; Une_Valeur : Integer := 0) is
    begin
        Postfixer (Lirelem (Un_Jeton, Une_Valeur));
    end Empiler;


    procedure Evaluer_Expression (La_Valeur : out Integer) is
    begin
        La_Valeur := Pilfact.Top (Pile).all;
        Pilfact.Pop (Pile);
    end Evaluer_Expression;


end Calcul;