The undef values in Perl
2013-12-02 15:24
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Varibels have the special undef value before they are first assigned, which is Perl's way of saying " nothing here to look at -- move alog, move alog."
If you use this "nothing" as a "numric something" , it will act like zero;
if you use this "nothing" as a "string something", it will act like nuil.
But it's better to definit the variables.
If you use this "nothing" as a "numric something" , it will act like zero;
if you use this "nothing" as a "string something", it will act like nuil.
But it's better to definit the variables.
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