diff --git a/bin/asa b/bin/asa
index 5b10944c..51f0c249 100644
--- a/bin/asa
+++ b/bin/asa
@@ -13,10 +13,11 @@ License:
 
 
 use strict;
+use warnings;
 
 exit 1 if grep {!-r} @ARGV;		# traditional
 
-if (grep /-/, @ARGV) {
+if (grep {/-/} @ARGV) {
 	$0 =~ s(.*/)();
 	warn "usage: $0 [filename ...]\n";
 	exit 2;						# traditional