Recognizer for dec-frac-const structures.
(dec-frac-constp x) → *
Function:
(defun dec-frac-constp (x) (declare (xargs :guard t)) (let ((__function__ 'dec-frac-constp)) (declare (ignorable __function__)) (and (mbe :logic (and (alistp x) (equal (strip-cars x) '(before after))) :exec (fty::alist-with-carsp x '(before after))) (b* ((before (cdr (std::da-nth 0 x))) (after (cdr (std::da-nth 1 x)))) (and (dec-digit-char-listp before) (dec-digit-char-listp after))))))
Theorem:
(defthm consp-when-dec-frac-constp (implies (dec-frac-constp x) (consp x)) :rule-classes :compound-recognizer)