Anoma Resource Machine Explainer in Long Form

[cwgoes]

@kike

• predicate of I_b prevents inclusion of another resource of the same kind in the same action
• resources belonging to different compliance units do not intersect. Namely, their commitments are different. (Here I would add, compliance units across all actions don’t intersect.)

Yes, that’s right: the predicates of I_0 and I_1 would not allow multiple $A$s to be included in a single action, and commitments/nullifiers cannot be duplicated across actions (to duplicate them would make the transaction invalid).

@kike

The second check is global. It can’t be enforced by any predicate whose domain is restricted to actions. Without this global check, one can never be sure that the same B is not used in a different action. So, if I’m not wrong, ‘exclusivity’ is currently guaranteed by a combination of local and global checks.

Yes. This global check is “always present” (not controlled by resource logics).

@kike

The question is then if we can generalize it. I think of the current situation as if all resources are flagged as ‘read-once’; these are resources that cannot appeare twice across the transaction. This decision is ‘hard-coded’ in the design. Can we make it a feature? I’m not sure how exactly, what comes to mind is via an always-public field in the resource that depending on its value the global check is enforced or not. This way, applications requiring ‘exclusivity’, like token swaps, and others that don’t require it can coexist.

This is similar to the lines I’m thinking along, but I think we may need to expose a somewhat more sophisticated interface, because it isn’t necessarily clear how to combine constraints: if a resource is used once with the flag set to “exclusive” and once with the flag set to “read-only”, should the transaction succeed or fail? Maybe what we want to prevent is multiple creations/consumptions with the “exclusive” flag. I think that it’s hard to make this decision without a clearer high-level semantics that we want to be able to use this low-level check to implement.