..is to explain undef and how you test for it.

Problem being 

my ($x,$y);
print "Same!" if $x==$y;
__END__
Same!

[download]
Since it doesnt follow the properties of the SQL null i'm not real sure why explaining undef will help any more than explaining an empty string.

Yves / DeMerphq
--
When to use Prototypes?

In reply to Re: Re: How do I test for a NULL string? by demerphq
in thread How do I test for a NULL string? by merlyn

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