		Search-engine friendly clone of the ACL2 documentation.

Sig->index

Get the index field from a sig.

Signature
(sig->index x) → index
Arguments: x — Guard (sig-p x).
Returns: index — Type (integerp index).

This is an ordinary field accessor created by defprod.

Definitions and Theorems

Function: sig->index$inline

(defun sig->index$inline (x)
  (declare (xargs :guard (sig-p x)))
  (declare (xargs :guard t))
  (let ((acl2::__function__ 'sig->index))
    (declare (ignorable acl2::__function__))
    (mbe :logic
         (b* ((x (and t x)))
           (ifix (cdr (std::da-nth 1 x))))
         :exec (cdr (std::da-nth 1 x)))))

Theorem: integerp-of-sig->index

(defthm integerp-of-sig->index
  (b* ((index (sig->index$inline x)))
    (integerp index))
  :rule-classes :rewrite)

Theorem: sig->index$inline-of-sig-fix-x

(defthm sig->index$inline-of-sig-fix-x
  (equal (sig->index$inline (sig-fix x))
         (sig->index$inline x)))

Theorem: sig->index$inline-sig-equiv-congruence-on-x

(defthm sig->index$inline-sig-equiv-congruence-on-x
  (implies (sig-equiv x x-equiv)
           (equal (sig->index$inline x)
                  (sig->index$inline x-equiv)))
  :rule-classes :congruence)