[poe] Constraint Narrative

simonstey has just created a new issue for https://github.com/w3c/poe:

== Constraint Narrative ==
> Constraints are used to express limitations, restrictions, or interpretations that are applied to these classes.

that's wrong, they are applied to instances of those classes not on the classes themselves -> remove entire sentence 

> Constraints can be represented as Atomic Constraints - in which the left and right operands are compared - or as Compound Constraints in which the left and right operands are existing Atomic Constraints, which are also compared. 

according to that, each compound constraint is also an atomic constraint

> A constraint is evaluated as a kind of "black box" from an external system 

no.. a constraint is evaluated as the constraint it is, it's the constraint evaluation that we treat as a black box.

> (e.g., any kind of reasoning engine), 

what? -> remove

> and the outcome of this evaluation is of the form true (if the constraint is satisfied) or false (if the constraint is not satisfied).

remove (it's also kinda weirdly phrased)

> ODRL Processors must check the satisfiability all constraints at the time of processing the relevant Action, Asset, and Party.

checking **satisfiability of** a constraint != checking whether a constraint **is satisfied** under a given interpretation ->

1. A OR B is satisfiable; there are interpretations that make A OR B true (e.g., whenever I(A) = 1 or I(B) = 1)
2. A OR B is not satisfied with I(A) = I(B) = 0

> If the constraint is satisfied then the action becomes valid for the enclosing Rule. If the constraint is not satisfied, then the action is not valid for the enclosing Rule.

+ what's the definition of a rule with an "invalid" action? 
+ what does that mean for parties/assets? 

> When multiple Constraints apply to the same Rule they are interpreted as conjunction. A Rule becomes effective if all of its Constraints are satisfied.

what if multiple constraints apply to the same party-/assetcollection?


Please view or discuss this issue at https://github.com/w3c/poe/issues/203 using your GitHub account

Received on Monday, 26 June 2017 10:54:12 UTC