text: function
  eval_draw(p)
  {
  	var F, X;
  	push_symbol(NIL); // return value
  	if (drawmode)
  		return;
  	F = cadr(p);
  	X = caddr(p);
  	if (!isusersymbol(X))
  		X = symbol(SYMBOL_X);
  	save_binding(X);
  	drawmode = 1;
  	draw(F, X);
  	drawmode = 0;
  	restore_binding(X);
  }
  