- (etypecase fcn
- (sb-kernel:byte-closure
- (set-function-name (sb-kernel:byte-closure-function fcn)
- new-name))
- (sb-kernel:byte-function
- (setf (sb-kernel:byte-function-name fcn) new-name))))
+ (error 'simple-type-error
+ :datum fcn
+ :expected-type 'generic-function
+ :format-control "internal error: bad function type"))