Check designator and marker equivalence together
by iterating over each concept's designator (which
consists of a literal, marker, or name) and testing
pCG value equivalence.
Is the first conceptual relation supertype compatible with the second?
For this to be true, the first's relation must be the same type or a
supertype of the second, and the same must hold for each concept
argument of the two conceptual relations.
Does this graph contain one or more actor relations?
This asks nothing about the validity of any such actors,
a task carried out at pCG actor definition time.
Expression productions **
Precedence of operators (from lowest to highest)
----------------------- Associativity
-------------
or L
and L
> < >= <= == != is (is: type equivalence operator) L
+ - L
* div mod L
- not (unary negation and logical complement) L
[] .
Return the sub-actor (actor or function) which is next ready to
to be executed by virtue of having all input concept designators
bound to pCG literals.