Maybe im totally missing the point, but the following will traverse a tree composed of hashes and return the path. 

sub path_to_op {
  my ($node,$tgt,$path)=@_;
  $path||='';
  return $path if $node==$tgt;
  
  foreach my $key (keys %$node) {
     my $path=path_to_op($node->{$key},$tgt,"$path{$key}");
     return $path if $path;    
  }
  return ''
}

[download]

But this seems so blindingly obvious to me that I'm having trouble believing I understand the question. After all I know you are very competent programmer so im at a loss to accept that I understand the question correctly....


---
demerphq

    First they ignore you, then they laugh at you, then they fight you, then you win.
    -- Gandhi

In reply to Re: Logic programming without using the RE engine as a crutch by demerphq
in thread Logic programming without using the RE engine as a crutch by diotalevi

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