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Sponge

Spongep

Recognizer for sponge structures.

Signature
(spongep x) → *

Definitions and Theorems

Function: spongep

(defun spongep (x)
  (declare (xargs :guard t))
  (let ((__function__ 'spongep))
    (declare (ignorable __function__))
    (and (mbe :logic (and (alistp x)
                          (equal (strip-cars x)
                                 '(stat mode index)))
              :exec (fty::alist-with-carsp x '(stat mode index)))
         (b* ((stat (cdr (std::da-nth 0 x)))
              (mode (cdr (std::da-nth 1 x)))
              (index (cdr (std::da-nth 2 x))))
           (and (nat-listp stat)
                (modep mode)
                (natp index))))))

Theorem: consp-when-spongep

(defthm consp-when-spongep
  (implies (spongep x) (consp x))
  :rule-classes :compound-recognizer)