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Location

Locationp

Recognizer for location structures.

Signature
(locationp x) → *

Definitions and Theorems

Function: locationp

(defun locationp (x)
  (declare (xargs :guard t))
  (let ((__function__ 'locationp))
    (declare (ignorable __function__))
    (and (consp x)
         (cond ((or (atom x) (eq (car x) :var))
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((name (std::da-nth 0 (cdr x))))
                       (identifierp name))))
               ((eq (car x) :tuple-comp)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 2)
                     (b* ((tuple (std::da-nth 0 (cdr x)))
                          (index (std::da-nth 1 (cdr x))))
                       (and (locationp tuple) (natp index)))))
               (t (and (eq (car x) :struct-comp)
                       (and (true-listp (cdr x))
                            (eql (len (cdr x)) 2))
                       (b* ((struct (std::da-nth 0 (cdr x)))
                            (name (std::da-nth 1 (cdr x))))
                         (and (locationp struct)
                              (identifierp name)))))))))

Theorem: consp-when-locationp

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