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Sig-p

Recognizer for sig structures.

Signature
(sig-p x) → *

Definitions and Theorems

Function: sig-p

(defun sig-p (x)
  (declare (xargs :guard t))
  (let ((acl2::__function__ 'sig-p))
    (declare (ignorable acl2::__function__))
    (and (mbe :logic (and (alistp x)
                          (equal (strip-cars x) '(module index)))
              :exec (fty::alist-with-carsp x '(module index)))
         (b* ((module (cdr (std::da-nth 0 x)))
              (index (cdr (std::da-nth 1 x))))
           (and (symbolp module)
                (integerp index))))))

Theorem: consp-when-sig-p

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