OK, there is a node out there called

How do I sort a hash (optionally by value instead of key)?

I was wondering how the logic works with the sort? When I write

foreach $invnumctr ( sort{$inv{$a} <=> $inv{$b}} keys %inv) {

how does perl know how to sort the list? How does the comparison work logically? I have included this in my code and i have solved my problem, but I feel uncomfortable not knowing what it is that the code is doing.

In reply to sort keys question by treebeard

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