add set_value API

diff --git a/lib/DX/SetOver.pm b/lib/DX/SetOver.pm
index 88a964d..74090bd 100644 (file)
--- a/lib/DX/SetOver.pm
+++ b/lib/DX/SetOver.pm
@@ -15,10 +15,14 @@ sub to_stream {
 
 sub with_value {
   my ($self, $value) = @_;
-  return ref($self)->new(
-    %$self,
-    values => { %{$self->values}, $value->${\$self->over} => $value }
-  );
+  return ref($self)->new(%$self, values => { %{$self->values} })
+                   ->set_value($value);
+}
+
+sub set_value {
+  my ($self, $value) = @_;
+  $self->values->{$value->${\$self->over}} = $value;
+  return $self;
 }
 
 1;