in reply to $array[ 'Infinity' ]
It prints only 5\n\n for me (with perl 5.8.8).
The $a['Infinity'] part is not surprising, because the string is coerced into an integer, which is 0.
I was quite surprised though that -Infinity is evaluated as -inf (and $a[-inf] is undef; no surprises here). A quick grep through the pod files in my perl distribution show that Infinity was introduced in perl561delta as a synonym for inf.
It's a bit weird that it dies under strict, IMHO.
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