Young one, see there are two of them comparison ways, the way of the erudite and the way of the counters. And it is said in our holy book, on the page with the number of 100, in its third incarnation, that: These operators return 1 for true and "" for false.. And also in this book, on the page with the number of 30, it is explained in the utmost detail that "" is one of the values considered to be false by this what we adore, the others being "0" and 0. And of all those values to choose from, only that what you questioned will prevent the demon inconsistencius from appearing. Since note this little transcript from the apocryphal writings of the heretic clemburg, who has repented and is one of us today, and understand, and be satisfied in your curiosity: 

> perl -le 'print ( undef == 0 ? "yes" : "no" )'
yes

> perl -le 'print ( undef == "0" ? "yes" : "no" )'
yes

> perl -le 'print ( undef == "" ? "yes" : "no" )'
yes

> perl -le 'print ( undef eq 0 ? "yes" : "no" )'
no

> perl -le 'print ( undef eq "0" ? "yes" : "no" )'
no

> perl -le 'print ( undef eq "" ? "yes" : "no" )'
yes

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Christian Lemburg
Brainbench MVP for Perl
http://www.brainbench.com

In reply to RE: Falsehoods & empty strings by clemburg
in thread Falsehoods & empty strings by Anonymous Monk

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