This is not a bug

Perl has magic increment operator, it works on strings

Perl not have magic decrement operator, so string is turned into a number

inf looks like a string so it is a string, not a number, use int to force numification 

 $ perl -MData::Dump -e " $f = inf; dd $f; $f--; dd $f; "
"inf"
1.#INF

$ perl -MData::Dump -e " dd int inf "
1.#INF

$ perl -MData::Dump -e " dd int Infinity  "
1.#INF

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perlnumber, perldata, 2010 :) Infinity and Inf?

In reply to Re: Incrementing "Infinity" bug (numification, perlnumber, magic increment decrement) by Anonymous Monk
in thread Incrementing "Infinity" bug by LanX

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