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Filtering-by-name

Vl-keep-descriptions

Signature
(vl-keep-descriptions names x) → filtered-x
Arguments: names — Names of vl-descriptions to keep.
Guard (string-listp names).; x — List to filter.
Guard (vl-descriptionlist-p x).
Returns: filtered-x — Type (vl-descriptionlist-p filtered-x).

Definitions and Theorems

Function: vl-keep-descriptions

(defun vl-keep-descriptions (names x)
 (declare (xargs :guard (and (string-listp names)
                             (vl-descriptionlist-p x))))
 (let ((__function__ 'vl-keep-descriptions))
  (declare (ignorable __function__))
  (mbe :logic
       (cond ((atom x) nil)
             ((member-equal (vl-description->name (car x))
                            (string-list-fix names))
              (cons (vl-description-fix (car x))
                    (vl-keep-descriptions names (cdr x))))
             (t (vl-keep-descriptions names (cdr x))))
       :exec
       (b* (((when (or (atom names) (atom x))) nil)
            ((unless (longer-than-p 10 names))
             (vl-slow-keep-descriptions names x))
            (fal (make-lookup-alist names))
            (ans (with-local-nrev
                      (vl-fast-keep-descriptions names fal x nrev)))
            (- (fast-alist-free fal)))
         ans))))

Theorem: vl-descriptionlist-p-of-vl-keep-descriptions

(defthm vl-descriptionlist-p-of-vl-keep-descriptions
  (b* ((filtered-x (vl-keep-descriptions names x)))
    (vl-descriptionlist-p filtered-x))
  :rule-classes :rewrite)

Theorem: vl-keep-descriptions-when-atom

(defthm vl-keep-descriptions-when-atom
  (implies (atom x)
           (equal (vl-keep-descriptions names x)
                  nil)))

Theorem: vl-keep-descriptions-of-cons

(defthm vl-keep-descriptions-of-cons
  (equal (vl-keep-descriptions names (cons a x))
         (if (member-equal (vl-description->name a)
                           (string-list-fix names))
             (cons (vl-description-fix a)
                   (vl-keep-descriptions names x))
           (vl-keep-descriptions names x))))

Theorem: member-equal-of-vl-keep-descriptions

(defthm member-equal-of-vl-keep-descriptions
  (iff (member-equal a (vl-keep-descriptions names x))
       (and (member-equal a (vl-descriptionlist-fix x))
            (member-equal (vl-description->name a)
                          (string-list-fix names)))))

Theorem: subsetp-equal-of-vl-keep-descriptions

(defthm subsetp-equal-of-vl-keep-descriptions
  (subsetp-equal (vl-keep-descriptions names x)
                 (vl-descriptionlist-fix x)))

Theorem: vl-keep-descriptions-when-atom-of-names

(defthm vl-keep-descriptions-when-atom-of-names
  (implies (atom names)
           (equal (vl-keep-descriptions names x)
                  nil)))

Theorem: vl-slow-keep-descriptions-removal

(defthm vl-slow-keep-descriptions-removal
  (equal (vl-slow-keep-descriptions names x)
         (vl-keep-descriptions names x)))

Theorem: vl-fast-keep-descriptions-removal

(defthm vl-fast-keep-descriptions-removal
  (equal (vl-fast-keep-descriptions names fal x nrev)
         (append nrev (vl-keep-descriptions names x))))

Theorem: vl-keep-descriptions-of-string-list-fix-names

(defthm vl-keep-descriptions-of-string-list-fix-names
  (equal (vl-keep-descriptions (string-list-fix names)
                               x)
         (vl-keep-descriptions names x)))

Theorem: vl-keep-descriptions-string-list-equiv-congruence-on-names

(defthm vl-keep-descriptions-string-list-equiv-congruence-on-names
  (implies (str::string-list-equiv names names-equiv)
           (equal (vl-keep-descriptions names x)
                  (vl-keep-descriptions names-equiv x)))
  :rule-classes :congruence)

Theorem: vl-keep-descriptions-of-vl-descriptionlist-fix-x

(defthm vl-keep-descriptions-of-vl-descriptionlist-fix-x
  (equal (vl-keep-descriptions names (vl-descriptionlist-fix x))
         (vl-keep-descriptions names x)))

Theorem: vl-keep-descriptions-vl-descriptionlist-equiv-congruence-on-x

(defthm
      vl-keep-descriptions-vl-descriptionlist-equiv-congruence-on-x
  (implies (vl-descriptionlist-equiv x x-equiv)
           (equal (vl-keep-descriptions names x)
                  (vl-keep-descriptions names x-equiv)))
  :rule-classes :congruence)

Subtopics

Vl-fast-keep-descriptions
Vl-slow-keep-descriptions