I don't see how the eq case is any more helpful than the logical-only operators..?
Perhaps we should ask then why logical-only operators ignore undef, but not why other operators don't ignore it.
I just think of the amount of code out there that is written to avoid those warnings.
Really?
a code to avoid warning and introduce bug: 
$x = '' unless defined($x)

[download]
a code to just avoid warning; 
my $x = '';

[download]
a code to avoid bug: 
defined($x) or confess;

[download]
So you see 1st case in your code?

a code with bug: 
mysub($user_data)
{
  $user_$data->{invoice_number} ...
}
mysub({age => $user_age, inovice_number = $invoice_number}) # TYPO!

[download]
a code which catches bug: 
mysub($user_data)
{
  defined($user_$data->{invoice_number}) or confess;
  $user_$data->{invoice_number} ...
}
mysub({age => $user_age, inovice_number = $invoice_number}) # TYPO!

[download]

In reply to Re^3: Do people find warning for undef with string compare useful? by vsespb
in thread Do people find warning for undef with string compare useful? by perl-diddler

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