http://qs321.pair.com?node_id=744245

I've been banging my head on the table with Apache::Session::MySQL today. Consider:

eval { ( my %session, $ok ); $ok = tie( %session, 'Apache::Session::MySQL', undef, ... ); if ( $ok ) { ... do something with %session ... } untie %session; }
This doesn't work from mod_perl, because the untie throws an exception following warning causes my web page to fail:
untie attempted while 1 inner references still exist at foo.pl line 250.
Since I don't use any explicit references to %session, this caught me by surprise. I have since resolved it; can you see the bug?

Updates:
  • clarified failure per note from ysth. Occasionally I use an english-ish idiom instead of a precise technical term.
  • The !! idiom may not be elegant to some, but I find it elegant because it can be read as "dammit," and I was looking for a -dammit flag to work around this failure :)
  • The use of $ok instead of the simple if statement occurred because of some additonal logic that I was doing after the tie, and before the untie. It had been omitted in this sample code.