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Branch-funct

Branch-funct-p

Recognizer for branch-funct structures.

Signature
(branch-funct-p x) → *

Definitions and Theorems

Function: branch-funct-p

(defun branch-funct-p (x)
  (declare (xargs :guard t))
  (let ((__function__ 'branch-funct-p))
    (declare (ignorable __function__))
    (and (consp x)
         (cond ((or (atom x) (eq (car x) :beq))
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 0)
                     (b* nil t)))
               ((eq (car x) :bne)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 0)
                     (b* nil t)))
               ((eq (car x) :blt)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 0)
                     (b* nil t)))
               ((eq (car x) :bltu)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 0)
                     (b* nil t)))
               ((eq (car x) :bge)
                (and (true-listp (cdr x))
                     (eql (len (cdr x)) 0)
                     (b* nil t)))
               (t (and (eq (car x) :bgeu)
                       (and (true-listp (cdr x))
                            (eql (len (cdr x)) 0))
                       (b* nil t)))))))

Theorem: consp-when-branch-funct-p

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