The type simple-condition represents conditions that are signaled by signal whenever a format-control is supplied as the function’s first argument.
The format control and format arguments are initialized with
the initialization arguments named :format-control
and :format-arguments
to make-condition, and are
accessed by the functions
simple-condition-format-control
and simple-condition-format-arguments. If format arguments are not supplied to make-condition, nil is used as a default.
simple-condition-format-control; simple-condition-format-arguments,
simple-condition-format-arguments