That's what subroutines are for. 
sub is_empty_string {
  my ($value) = @_;
  defined $value and $value eq '';
}

if (is_empty_string $params->{root} ) {
}

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"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: complaint: always testing defined() by Joost
in thread complaint: always testing defined() by RaptorRex

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