diff --git a/Shorewall-perl/Shorewall/Macros.pm b/Shorewall-perl/Shorewall/Macros.pm
index 4e806732d..78b89db46 100644
--- a/Shorewall-perl/Shorewall/Macros.pm
+++ b/Shorewall-perl/Shorewall/Macros.pm
@@ -112,7 +112,7 @@ sub merge_macro_source_dest( $$ ) {
 sub merge_macro_column( $$ ) {
     my ( $body, $invocation ) = @_;
 
-    if ( defined $invocation and $invocation ne '' ) {
+    if ( defined $invocation && $invocation ne '' ) {
 	return ( $body || '') if $invocation eq '-';
 	$invocation || '';
     } else {