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Fgl-rule

Fgl-rule-p

Recognizer for fgl-rule structures.

Signature
(fgl-rule-p x) → *

Definitions and Theorems

Function: fgl-rule-p

(defun fgl-rule-p (x)
  (declare (xargs :guard t))
  (let ((__function__ 'fgl-rule-p))
    (declare (ignorable __function__))
    (and (consp x)
         (cond ((or (atom x) (eq (car x) :rewrite))
                (and (consp (cdr x))
                     (b* ((rune (car (cdr x)))
                          (rule (cdr (cdr x))))
                       (and (fgl-rune-p rune)
                            (cmr::rewrite-p rule)))))
               ((eq (car x) :primitive)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 1)
                     (b* ((name (std::da-nth 0 (cdr x))))
                       (pseudo-fnsym-p name))))
               (t (and (eq (car x) :meta)
                       (and (true-listp (cdr x))
                            (eql (len (cdr x)) 1))
                       (b* ((name (std::da-nth 0 (cdr x))))
                         (pseudo-fnsym-p name))))))))

Theorem: consp-when-fgl-rule-p

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