1) why/how does it skip the dupe?

It actually doesn't skip it. It's just that it is assigned as a key to a hash, and hash keys are unique, thus it overwrites the old key without doing harm.

2) what does assigning the 1 do?

It's just a random value, you could assign anything you like as a value to the hash. It's not important, as long as there's something there to make perl happy.

3) what does that 2nd line do to delete the key/value pairs of page => 1?

nothing. It now restores the AoH. Hmm, I didn't tidy up the "%uniq" hash if you thought of that.

Also, any good sources for learning how to disect a map/grep

Besides   perldoc -f grep   and perldoc -f map? Hmm. Reading Perlmonks... ;)

Cheers, Sören

In reply to Re^3: Is there better way to delete dups in an AoH? by Happy-the-monk
in thread Is there better way to delete dups in an AoH? by bradcathey

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