package body file is
  procedure enfiler(f: in out MaFile; e : integer) is
  begin
    if filePleine(f) then
      raise Erreur_FilePleine;
    end if;
    
    f.data(f.queue) := e;
    f.queue := f.queue + 1;
    f.size := f.size + 1;
    if f.queue > maxsize_file then
      f.queue := 1;
    end if;
  end;
  
  procedure defiler(f: in out MaFile) is
  begin
    if fileVide(f) then
      raise Erreur_FileVide;
    end if;
    
    f.head := f.head + 1;
    f.size := f.size - 1;
    if f.head > maxsize_file then
      f.head := 1;
    end if;
  end;
  
  function tete(f: in MaFile) return integer is
  begin
    return f.data(f.head);
  end;
  
  function fileVide(f: in MaFile) return Boolean is
  begin
    return f.size = 0;
  end;
  
  function filePleine(f: in MaFile) return Boolean is
  begin
    return f.size = maxsize_file;
  end;
end file;