		Search-engine friendly clone of the ACL2 documentation.

Char-val

Char-val-p

Recognizer for char-val structures.

Signature
(char-val-p x) → *

Definitions and Theorems

Function: char-val-p

(defun char-val-p (x)
  (declare (xargs :guard t))
  (let ((__function__ 'char-val-p))
    (declare (ignorable __function__))
    (and (consp x)
         (cond ((or (atom x) (eq (car x) :sensitive))
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((get (std::da-nth 0 (cdr x))))
                       (common-lisp::stringp get))))
               (t (and (eq (car x) :insensitive)
                       (and (true-listp (cdr x))
                            (eql (len (cdr x)) 2))
                       (b* ((iprefix (std::da-nth 0 (cdr x)))
                            (get (std::da-nth 1 (cdr x))))
                         (and (booleanp iprefix)
                              (common-lisp::stringp get)))))))))

Theorem: consp-when-char-val-p

(defthm consp-when-char-val-p
  (implies (char-val-p x) (consp x))
  :rule-classes :compound-recognizer)