> -----Original Message-----
> From: D. Martin [mailto:[EMAIL PROTECTED]
> Sent: Monday, February 09, 2004 8:32 PM
> To: [EMAIL PROTECTED]
> Subject: [Templates] The Nature of Truth (in TT2)
>
>
> Hello,
>
> I have a question about the nature of truth (in TT2). I am
> finding that
> empty arrays passed from my module always test true in my
> templates and
> that I have to use [% IF myArray.size > 0 %] rather than [% IF myArray
> %] to test whether to take action on array data. The following sub and
> template snippet demonstrated the problem. Both empty_array and
> empty_ref test true in my template conditionals.
>
> Is this the intended behavior?
>
> TIA,
>
> David Martin
David:
That's the behavior of perl itself. A reference to something evaluates to
true, even if that something is empty:
foreach my $ref ([],{},\''){
print 'reference to an empty ' . ref($ref) . ' evaluates to ';
$ref ? print "true\n" : print "false\n";
}
outputs:
reference to an empty ARRAY evaluates to true
reference to an empty HASH evaluates to true
reference to an empty SCALAR evaluates to true
Also, in your example, empty_array is a reference to an empty array, not an
actual array.
Perhaps code your sub routines or methods to return undef, rather than a
reference to an empty something.
Mike
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