I have what I think is not a unique problem, just one that I cannot seem to successfully solve.

I have a hash of hashes, to N levels deep (usually around 8 to 10). Each hash has some normal hash items, and one is the one with the deep children, at each level. The deep one always has a numeral for a key, so /\d+/ works to find it.

Anyhow, I need a routine that will recurse through the hash, starting at the top, looking for a particular key number. If found, I need it to return THAT value.

I've been writing a recursive subroutine, but it seems to fail.

Here it is:
my ($newtop,$error) = _get_top($wanted_number,$tippy_top_hash);

and

sub _get_top {
  my $top_req = shift;
  my $top_item    = shift;
  
  if ($top_item->{'ctl_id'} == $top_req) {
    return ($top_item,undef);
  }
  
  ## Added for speed
  if (exists($top_item->{$top_req})) {
    return($top_item->{$top_req},undef);
  }
  ## End added for speed
  
  foreach my $key (keys %{$top_item}) {
    next unless ($key =~ /^\d+/);
    if ($key == $top_req) {
      return ($top_item->{$key},undef);
      last;   ### probably not needed
    } else {
      _get_top($top_req, $top_item->{$key});
    }
    return (undef,"Seems we can't get the top item hash!");
  }
  
}

[download]
This is failing miserably, always returning undef,"Seems . . ."
Liberal prints to STDERR reveals that it does find the wanted hash item, but continues on below it!
If any of you geniouses out there can help, I would greatly appreciate it.

What does THIS little button do . .<Click>; "USER HAS SIGNED OFF FOR THE DAY"

In reply to Recursing a hash by tame1

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