sub outer {
  my $x;
  $x=shift;

  sub inner {
    print "x is $x\n";
  }
}
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A little background: I have a class (let's call it Node.pm) that uses another class (Cache.pm) to cache calls to and from the DBI handler. Something like this pseudo-code:

package Node;

use Cache;

my $cache=new Cache;

sub new {
  ## blah blah
  $self;
}

sub get {
  my $self=shift;
  my $id=shift;
  if (my $data=$cache->check($id)) {
     return $data;
  }
  ## blah blah
}

1;
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The concept is that regardless of how many instances of Node:: that you create, the same Cache:: object will be used to improve performance.

This is wonderful until I converted the app to work under mod_perl. Now I can't figure out a way of maintaining a single cache for all instances.

Using use vars qw($cache) is fine to preserve the dynamic nature of $cache, but it keeps the $cache object alive across invocations of CGI (which is A Bad Thing because another thread might have modified the object and this instance has no knowledge of it).

What I want is for $cache to behave like it would under a normal CGI; it's created at the beginning of the execution of the script and dies at the end.

If this was in the main cgi-bin and not a class, I could do something like:

{
   $cache=new Cache;
}

## everything

{
   undef $cache;
}
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But this won't work inside a module (because mod_perl only executes the class once when loading it for the first time).

Assuming this was moderately understandable (which I doubt), does anyone have any suggestions or ideas?