		Search-engine friendly clone of the ACL2 documentation.

Hex-quad

Hex-quad-p

Recognizer for hex-quad structures.

Signature
(hex-quad-p x) → *

Definitions and Theorems

Function: hex-quad-p

(defun hex-quad-p (x)
  (declare (xargs :guard t))
  (let ((__function__ 'hex-quad-p))
    (declare (ignorable __function__))
    (and (mbe :logic (and (alistp x)
                          (equal (strip-cars x)
                                 '(1st 2nd 3rd 4th)))
              :exec (fty::alist-with-carsp x '(1st 2nd 3rd 4th)))
         (b* ((1st (cdr (std::da-nth 0 x)))
              (2nd (cdr (std::da-nth 1 x)))
              (3rd (cdr (std::da-nth 2 x)))
              (4th (cdr (std::da-nth 3 x))))
           (and (hex-digit-char-p 1st)
                (hex-digit-char-p 2nd)
                (hex-digit-char-p 3rd)
                (hex-digit-char-p 4th))))))

Theorem: consp-when-hex-quad-p

(defthm consp-when-hex-quad-p
  (implies (hex-quad-p x) (consp x))
  :rule-classes :compound-recognizer)