ESSENCE — CRUD on Activities

Problem to be solved: The spec allows Activities to perform four operations (create, read, update, delete) on a Work Product or an Alpha. The card just names input and output, which is less specific. Activity Spaces just allow input, which seems very limited. In general, the language spec seems unbalanced with respect to this aspect.

Proposed solution:

• Remove association “input” from language element “ActivitySpace”.
• Remove language element “Action” and all its associations.
• Add associations “input” and “output” from language element “AbstractActivity” to “Alpha”.
• Add associations “input” and “output” from language element “Activity” to “WorkProduct”.

ActivitySpace is not in the position to create Alphas, it is merely importing them, acting like a containment, not a factory. Activities, on the other hand, are capable to influence the lifecycle of Alphas. Rearranging the Associations would distort this distinction. Also, the suggested removal of Action would remove the ability to specify the intended action on Aplhas and WorkProducts. The model as it stands is correct and shall not be changed.