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Re^7: Hash key composition with a comma?

by LanX (Cardinal)
on Mar 18, 2018 at 10:16 UTC ( #1211181=note: print w/replies, xml ) Need Help??

in reply to Re^6: Hash key composition with a comma?
in thread Hash key composition with a comma?

Yes that's pretty much the example I came up with, only after thinking hard.

"Karl-Heinz Urban" and "Karl Heinz-Urban" would get the same entry for $age{$first,$family} if $; was "-" and consequently a Hollywood actor would change age. (This never happens normally ;)

But you first need to construct such a collision which results in data loss.

Intuition (and AM) says "one injected delimiter and it breaks" like $b='x"y';eval qq {$a="$b"} breaks.

But that's not the case, you need a coincidence where both keys are polluted in a very specific way.

And a hash with polluted entries will continue to work normally as long as Mr "Heinz-Urban" doesn't show up.

I'd like to see a more believable scenario.

NB: Of course I wouldn't allow polluted keys in the first way.

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Wikisyntax for the Monastery

PS : AM is thanking you for doing his "homework"! ;)

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