One of the major limitations I found while using Guvnor (and I’m relative new to Guvnor) was the impossibility to change the Patterns/Action order while authoring rules. You ought to be very careful about the order of your patterns otherwise you would end up removing 3 patterns (that took you about 3 minutes to create) because you forgot one little Pattern at the beginning!
Well my friends, those times have end! A new feature available in Guvnor 5.1M2 is the possibility to change the order of your Patterns and Actions. Each Pattern or Action now have a toolbar in the right side. This toolbar contains 3 buttons:
The first button will open the “Insert Pattern/Action” popup and add a new Pattern/Action just after the current Pattern/Action. The other two buttons (the arrows) will move up/down the current Pattern/Action.
When using the “plus” icon next to the WHEN or THEN part, the opened popup will contain a dropdown list to select the order where the new Pattern/Action will be added:
You can see this improvement in action in the following screencast: http://www.plugtree.com/downloads/screencasts/01-Pattern_Action_Position.htm
The only limitation is that you can only change the order of “first order” Patterns/Actions. It doesn’t work for nested elements yet.