Hmm, I thought your code was idempotent: it would find the parts in any location of the string. So it should swollow the parts in the wrong order, or you can try the parts in any order. You delete out of the string each one you find, so anything left is stuff you didn't recognise and that causes an error, when you're done with everything you do know.

If it's not, get rid of the ^ and give it a spin.

—John

P.S. it's the to_string you want the correct order for, right? That wasn't part of the original problem, but that's not a problem:

@value_sorted_keys= sort { $x{a} <=> $x{b} } (keys %x);
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