condition—a condition of type simple-condition.
format-control—a format control.
format-arguments—a list.
simple-condition-format-control returns the format control needed to
process the condition's format arguments.
simple-condition-format-arguments returns a list of format arguments
needed to process the condition's format control.
(setq foo (make-condition 'simple-condition
:format-control "Hi ~S"
:format-arguments '(ho)))
→ #<SIMPLE-CONDITION 26223553>
(apply #'format nil (simple-condition-format-control foo)
(simple-condition-format-arguments foo))
→ "Hi HO"