		Search-engine friendly clone of the ACL2 documentation.

Function-definer

Function-definerp

Recognizer for function-definer structures.

Signature
(function-definerp x) → *

Definitions and Theorems

Function: function-definerp

(defun function-definerp (x)
  (declare (xargs :guard t))
  (let ((__function__ 'function-definerp))
    (declare (ignorable __function__))
    (and (consp x)
         (cond ((or (atom x) (eq (car x) :regular))
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 2)
                     (b* ((body (std::da-nth 0 (cdr x)))
                          (measure (std::da-nth 1 (cdr x))))
                       (and (expressionp body)
                            (maybe-expressionp measure)))))
               (t (and (eq (car x) :quantified)
                       (and (true-listp (cdr x))
                            (eql (len (cdr x)) 3))
                       (b* ((quantifier (std::da-nth 0 (cdr x)))
                            (variables (std::da-nth 1 (cdr x)))
                            (matrix (std::da-nth 2 (cdr x))))
                         (and (quantifierp quantifier)
                              (typed-variable-listp variables)
                              (expressionp matrix)))))))))

Theorem: consp-when-function-definerp

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