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Function-output

Function-outputp

Recognizer for function-output structures.

Signature
(function-outputp x) → *

Definitions and Theorems

Function: function-outputp

(defun function-outputp (x)
  (declare (xargs :guard t))
  (let ((__function__ 'function-outputp))
    (declare (ignorable __function__))
    (and (consp x)
         (eq (car x) :function-output)
         (mbe :logic (and (alistp (cdr x))
                          (equal (strip-cars (cdr x))
                                 '(reg type)))
              :exec (fty::alist-with-carsp (cdr x)
                                           '(reg type)))
         (b* ((reg (cdr (std::da-nth 0 (cdr x))))
              (type (cdr (std::da-nth 1 (cdr x)))))
           (and (regaccessp reg)
                (value-typep type))))))

Theorem: consp-when-function-outputp

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