Source: Model Driven Solutions ( Ed Seidewitz)
There are many cases in the kernel in which the completion criteria for an activity space include multiple states for the same alpha. But, from the definition of "completion criterion” in the language, it is unclear what it means to have to complete multiple states for the same alpha. It seems redundant, since when you achieve a later state, it is assumed that all earlier states have already been met.
Reported: Essence 1.0 — Fri, 23 Jan 2015 20:52 GMT
Disposition: Resolved — Essence 1.1
Add entry criteria and update completion criteria
The states currently listed as "completion criteria" a kernel activity space are those states to which various alphas may be progressed by activities considered to be within the activity space. This is useful information, but it is confusing to refer to them all as "completion criteria", since some are really intermediate states of an alpha that must be progressed further before the activity space can truly be considered "complete".
For alphas that are expected to be progressed from some starting state to some final state by activities within an activity space, it would seem more correct to list the starting state of the alpha as an entry criterion for the activity space and the final state as a completion criterion. The problem with this is that the current language definition of entry criteria for an activity or an activity space seems to indicate that all the entry criteria must be fulfilled before the activity or activity space can start (logical "and" of the criteria). But this is not what is desired for an activity space, because an activity within an activity space will be able to start progressing alphas within the context of that activity space as long as the entry criteria for that activity are fulfilled, even if alphas unrelated to the activity have not reached the entry criterion state required for the activity space.
Therefore, the proposal for resolution of this issue is as follows:
1. Update the language definition of EntryCriterion to make it clear that work of an activity space can start when "one or more of its entry criteria are fulfilled" (logical "or" of entry criteria).
2. Update the kernel specifications for activity spaces to only list the final state of each alpha in the completion criteria (do not list intermediate states).
3. Update the kernel specifications for activity spaces to add entry criteria listing the required initial states of relevant alphas (these will be a subset of the input alphas for the activity space).
Updated: Fri, 2 Oct 2015 15:41 GMT