I have a hash that has a number of items in it. Example: 
[LOOP NEEDED HERE] {
  ...
  $links{$url}{html} = $html;
  ...
    $links{$new_url} = 1;
  ...

  $links{$url}{visited} = 1;
  ...
}

[download]

Note from my somewhat cryptic snippet above, that new $links keys can/will be created but they will not have a defined (yet) {visited} key. I guess this is sort of what is called a recursive loop? As new items are added, I need to make sure that those items are also dealt with.

What I'm looking for is some sort of loop syntax that will evaluate the $links hash entries to see whether or not the {visited} key is not defined > I can then "visit" the $url and then set $links{$url}{visited} = 1.

TIA

======================
Sean Shrum
http://www.shrum.net

In reply to Creating loop on undefined hash key value by S_Shrum

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