relationship.rb in acts-as-joinable-0.1.7.5

- old
+ new

@@ -1,3 +1,17 @@
 class ActsAsJoinable::Relationship < ActiveRecord::Base
   acts_as_relationship
-end
\ No newline at end of file
+  
+  def swap_parent_and_child
+    old_parent_type   = self.parent_type
+    old_parent_id     = self.parent_id
+    old_child_type    = self.child_type
+    old_child_id      = self.child_id
+
+    self.parent_type  = old_child_type
+    self.parent_id    = old_child_id
+    self.child_type   = old_parent_type
+    self.child_id     = old_parent_id
+
+    self.save!
+  end
+end