fset-value [Function]


The fset-value function replaces the current value of a given role on a given instance. It is faster than set-value because it does no error checking or argument coercion.


fset-value instance role value


The instance argument is the instance whose role value is to be changed.

The role argument is a relation, or the name of a relation.

The value argument is the new value of role. If role is single-valued and value is a list, the list is interpreted as a single role filler. If role is multiple-valued, then value must be a list, and each member of the list is interpreted as a separate filler.


The fset-value function returns value.


(defrelation r :characteristics :single-valued) 
(fset-value (fi Joe) (fr r) '(3 4 5)) ==> (3 4 5) 
(fset-value (fi Joe) (fr r) (fi Sue)) ==> |I|SUE 
(defrelation rr) 
(fset-value (fi Joe) 'rr (list (fi Mary) (fi Sue))) ==> (|I|MARY |I|SUE)

See Also

Last modified: Jun 1 1995