You can't get a reference to a call. But you can wrap the call into a small function: 
my $downloader = eval { new Downloader() } or die($@);

my $thread1 = threads->new(
   sub {
      $downloader->fetch("http://www.webaddress.com", \%siteHash);
   }
);

$thread1->join;

[download]

The (anonymous) sub will close over $downloader and %siteHash (assuming they are both lexical (my) variables), so they will be accessible to the sub even if they go out of scope.

By the way, I changed die(@_) to die($@). Check perlvar if you're not sure which to use.

In reply to Re: Object Functions and Threading by ikegami
in thread Object Functions and Threading by ramblinpeck

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