[henshin-dev] Challenges concerning legacy code with AmalgamationUnits

[Riegerf@xxxxxxxxxxxxxxxxxxxxxxx]

In the 2011 model, AmalgamationUnits will no longer exist and are  
replaced by Rules with nested Rules. The semantics will not change, so  
there is an easy transformation from the old to the new model which  
will be done automatically.

However, there is one rather significant change: The AmalgamationUnit  
will no longer be contained in the "TransformationUnits" container,  
but the "Rules" container. This will inevitably lead to a problem in  
legacy code which has to be solved somehow: Currently,  
AmalgamationUnits are loaded by using findUnitByName; in the 2011  
model, they will be loaded by using findRuleByName. FindUnitByName  
will no longer work, as they will be contained in the "Rules" container.

In order to preserve legacy code compatibility, I propose modifying  
findUnitByName, so it will also return Rules. This way, legacy code  
using findUnitByName for AmalgamationUnits will not have to be changed.

Felix