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Const

Constp

Recognizer for const structures.

Signature
(constp x) → *

Definitions and Theorems

Function: constp

(defun constp (x)
  (declare (xargs :guard t))
  (let ((__function__ 'constp))
    (declare (ignorable __function__))
    (and (consp x)
         (cond ((or (atom x) (eq (car x) :int))
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((unwrap (std::da-nth 0 (cdr x))))
                       (iconstp unwrap))))
               ((eq (car x) :float)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((unwrap (std::da-nth 0 (cdr x))))
                       (fconstp unwrap))))
               ((eq (car x) :enum)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((unwrap (std::da-nth 0 (cdr x))))
                       (identp unwrap))))
               (t (and (eq (car x) :char)
                       (and (true-listp (cdr x))
                            (eql (len (cdr x)) 1))
                       (b* ((unwrap (std::da-nth 0 (cdr x))))
                         (cconstp unwrap))))))))

Theorem: consp-when-constp

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