Hi all, today I'd like to ask about one think I really never understood about Perl'S sort function. We note the way we want sort to happen by telling how $a and $b are to be compared: 
$a <=> $b
$a->{hashkey}[index] cmp $b->{hashkey}[index]

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and so on. Why do we have to specify the same operation for $a and $b? Is there a case in which we would specify something else for $a than for $b? If not, why the redundancy?

In reply to Notation of sort function by Alphaphi

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