return 0 is unnecessary

Author: maybebyte

genblock

@@ -45,7 +45,7 @@ EOT
 }
 
 sub is_domain {
-my $potential_domain = shift or return 0;
+my $potential_domain = shift or return;
 
 if (
 $potential_domain =~ /
@@ -125,7 +125,7 @@ sub is_domain {
 {
 return ${^MATCH};
 }
-return 0;
+return;
 }
 
 # Given a hash reference, we "reduce" fully-qualified domains by
@@ -170,7 +170,7 @@ sub reduce_domains {
 }
 
 sub unique_domains {
-my $hashref = shift or return 0;
+my $hashref = shift or return;
 my $number_of_domains_added = 0;
 
 PROCESS_LINE: while ( <<>> ) {