--- trunk/Estraier.pm	2006/01/28 18:19:47	97
+++ trunk/Estraier.pm	2006/01/28 19:18:13	98
@@ -370,7 +370,7 @@
 
 package Search::Estraier::Condition;
 
-use Carp qw/confess croak/;
+use Carp qw/carp confess croak/;
 
 use Search::Estraier;
 our @ISA = qw/Search::Estraier/;
@@ -448,30 +448,71 @@
 
 =head2 set_options
 
-  $cond->set_options( SURE => 1 );
+  $cond->set_options( 'SURE' );
+
+  $cond->set_options( qw/AGITO NOIDF SIMPLE/ );
+
+Possible options are:
+
+=over 8
+
+=item SURE
+
+check every N-gram
+
+=item USUAL
+
+check every second N-gram
+
+=item FAST
+
+check every third N-gram
+
+=item AGITO
+
+check every fourth N-gram
+
+=item NOIDF
+
+don't perform TF-IDF tuning
+
+=item SIMPLE
+
+use simplified query phrase
+
+=back
+
+Skipping N-grams will speed up search, but reduce accuracy. Every call to C<set_options> will reset previous
+options;
+
+This option changed in version C<0.04> of this module. It's backwards compatibile.
 
 =cut
 
 my $options = {
-	# check N-gram keys skipping by three
 	SURE => 1 << 0,
-	# check N-gram keys skipping by two
 	USUAL => 1 << 1,
-	# without TF-IDF tuning
 	FAST => 1 << 2,
-	# with the simplified phrase
 	AGITO => 1 << 3,
-	# check every N-gram key
 	NOIDF => 1 << 4,
-	# check N-gram keys skipping by one
 	SIMPLE => 1 << 10,
 };
 
 sub set_options {
 	my $self = shift;
-	my $option = shift;
-	confess "unknown option" unless ($options->{$option});
-	$self->{options} ||= $options->{$option};
+	my $opt = 0;
+	foreach my $option (@_) {
+		my $mask;
+		unless ($mask = $options->{$option}) {
+			if ($option eq '1') {
+				next;
+			} else {
+				croak "unknown option $option";
+			}
+		}
+		$opt += $mask;
+	}
+	$self->{options} = $opt;
 }