This could very obviously be done with loops, but I'd like to know if there's a way in Perl to avoid that. My first attempt was this:

@interestingThings = ($root[2][0..3][3]);

# Should print an array of interesting scalar values.
print Dumper(\@interestingThings);

[download]

For those who understand a bit of CSS, I basically want to do something like #aUniqueElement p .anotherElement:;, where I describe sets of elements with a selector the describes their place in the DOM.

But if you're not familiar with CSS, here's a more detailed description of my problem:

Suppose I have a complex tree structure, comprised of arrays and hashes and references to tie them together. The structure has this property:

For any subtree rooted at N, any subtree rooted at X, such that X is a sibling of N, has the same shape as N.

This property means that we could talk about sets of nodes or subtrees by describing patterns of paths to them. For example, we could describe the set of nodes that are the third child of any of the children of the second child of the root. Or, succinctly: Tree->2nd Child->Nth Child->3rd Child, where N is in the range of Tree->2nd Child.

I want to collect such a set, though I'm actually interested in the values of nodes I'm describing.

Thanks very much!

In reply to How I can collect values out of complex tree structure that are located at chained keys matching a pattern? Without using a loop, that is. by Anonymous Monk

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