I'll bite... this concept of "commensurablity" is not one I grasp from your email.
"functions are (sugarably) degenerate (many to 1) relations and procedures are (sugarably) degenerate (state-transition) functions." Perl & many other languages don't have a strong distinction between functions & procudures (as I'm sure you know), a "function" is a subroutine returning a scalar, a "procedure" is a subroutine with no return value, side-effects only. A subroutine returning many values- a parcel of containers, perhaps, or an iterator, etc- is a "many-to-many" relation. I understand "relational algebra" from decades of SQL work, and have seen ORM's replicate relations in object systems with some success. What's missing for creating a relational wonderland in perl6? (Also: "a ton of apples should _not_, in general, be added to 3000 kg of oranges"- unless I operate a refrigerated shipping line, in which case all I care is that they are subclasses of "perishables"... Adding an acre of orchard to a season in the sun might be less "commensurable", though they could both be subclasses of "gifts to a lucky winner"... hmmm... what was the point again?)
