The VALUE-TYPE of a binary relation R with respect to a given
instance d is a constraint on the values of R when R is applied to d.
The constraint is specified as a class T such that when R(d,t) holds,
t is an instance of T.
- Arity: 3
(Nth-Domain Value-Type 3 Class)
(Nth-Domain Value-Type 2 Binary-Relation)
(<=> (Value-Type ?Instance ?Binary-Relation ?Type)
(And (Binary-Relation ?Binary-Relation)
(=> (Holds ?Binary-Relation ?Instance ?Value)
(Instance-Of ?Value ?Type)))))
- VALUE-TYPE is convenient for specifying type restrictions
on slots relative to a class by using the class's instance
- See-Also: slot-value-type