bugsbunny has asked for the wisdom of the Perl Monks concerning the following question:

I'm twig'ing a XML file (with XML::Twig via callback function).In the element handler I can extract parent-tag-id.
My question is how to build a HASH so that with only one check I can see if some element is a child to a specfic parent..
I thought of something in the lines of :
$hash{element} =~ /$parentID/
What I thought, is a string with ID's of all parents (for the element), the problem then is that this can be time&memory consuming to buid it..
I mean if it is more time&memory consuming to build such a structure, then it is better not to do it, but instead walk the tree from element-to->top-parent to see if it is a child, at the moment I'm doing the comparison..
I'm talking for gnuCash xml-file gnc:account tags handler.
in most of the cases account hierarcy dont go more than 3-4 level deep..