set("figure_style","new") /// @@prerequisite affectations 
plot2d([],[],rect=[-2,2;-2,2]);/// @@prerequisite affectations 
xrect(0,0,0.5,0.5);/// @@prerequisite affectations 
r=get("hdl");/// @@prerequisite affectations 

h=get("current_figure"); /// \sleftarrow{\normalfont handle to the default graphic window }
ch = h.children;/// \sleftarrow{\normalfont the Axes entities }
ch == get('current_axes') /// \sleftarrow{\normalfont the same ?  }
r1= ch.children;/// \sleftarrow{\normalfont graphic entities  }
r1== r /// \sleftarrow{\normalfont we have found the rectangle again  }