my $HELM_LIBRARY_DIR = $ENV{"HELM_LIBRARY_DIR"};
# this should be the only fixed constant
my $DEFAULT_HELM_LIBRARY_DIR = "@DEFAULT_HELM_LIBRARY_DIR@";
-if (defined ($HELM_LIBRARY_DIR) {
+if (defined ($HELM_LIBRARY_DIR)) {
$HELM_LIBRARY_PATH = $HELM_LIBRARY_DIR."./configuration.pl";
} else {
$HELM_LIBRARY_PATH = $DEFAULT_HELM_LIBRARY_DIR."./configuration.pl";