Recognizer for maybe-rational structures.
(maybe-rationalp x) → *
Function:
(defun maybe-rationalp (x) (declare (xargs :guard t)) (let ((__function__ 'maybe-rationalp)) (declare (ignorable __function__)) (cond ((not x) (b* nil t)) (t (b* ((fty::val x)) (rationalp fty::val))))))