I would advice against using and in this context, because later someone (you) may add an innocent return .... 

sub is_empty_string {
  my ($value) = @_;
  return defined $value and $value eq '';
}

[download]

I think && is more appropriate here:

sub is_empty_string {
  my ($value) = @_;
  return defined($value) && $value eq '';
}

[download]

In reply to Re^2: complaint: always testing defined() by roman
in thread complaint: always testing defined() by RaptorRex

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