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Value

Valuep

Recognizer for value structures.

Signature
(valuep x) → *

Definitions and Theorems

Function: valuep

(defun valuep (x)
  (declare (xargs :guard t))
  (let ((__function__ 'valuep))
    (declare (ignorable __function__))
    (and (consp x)
         (cond ((or (atom x) (eq (car x) :number))
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((get (std::da-nth 0 (cdr x))))
                       (acl2-numberp get))))
               ((eq (car x) :character)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((get (std::da-nth 0 (cdr x))))
                       (characterp get))))
               ((eq (car x) :string)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((get (std::da-nth 0 (cdr x))))
                       (stringp get))))
               ((eq (car x) :symbol)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((get (std::da-nth 0 (cdr x))))
                       (symbol-valuep get))))
               (t (and (eq (car x) :cons)
                       (and (true-listp (cdr x))
                            (eql (len (cdr x)) 2))
                       (b* ((car (std::da-nth 0 (cdr x)))
                            (cdr (std::da-nth 1 (cdr x))))
                         (and (valuep car) (valuep cdr)))))))))

Theorem: consp-when-valuep

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