+ ,@(when bit-frob
+ `((simple-bit-vector
+ (if (and (eq #'identity key)
+ (or (eq #'eq test)
+ (eq #'eql test)
+ (eq #'equal test)))
+ (let ((p (%bit-position (the bit item) sequence
+ from-end start end)))
+ (if p
+ (values item p)
+ (values nil nil)))
+ (vector*-frob sequence)))))
+ (t
+ (vector*-frob sequence))))