sub wrap_render {
  local $x=shift;
  local $y=shift;
  if ($var) {
    return "your change";
  } else
    return render();
  }
}

##</code><code>##

sub render_a {
  print "<a ";
  print "style='$css'" if $global_css_flag;
  print ">"
}

##</code><code>##

sub render_a {
  my $style=get_css();
  print "<a $style>";
}
 
{ my $css_flag;
  sub get_css {
    return "style='$css'" if $css_flag;
  }
  sub css_flag { if (@_) {$css_flag=shift} else {$css_flag} }  # getter-setter
}