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• Characters
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Character-listp

Recognizer for a true list of characters

The predicate character-listp tests whether its argument is a true list of characters.

Function: character-listp

(defun character-listp (l)
       (declare (xargs :guard t))
       (cond ((atom l) (equal l nil))
             (t (and (characterp (car l))
                     (character-listp (cdr l))))))

Subtopics

Std/typed-lists/character-listp

Lemmas about character-listp available in the std/typed-lists library.

Character-list-fix

Inline fixing function for character lists.