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Function

Functionp

Recognizer for function structures.

Signature
(functionp x) → *

Definitions and Theorems

Function: functionp

(defun functionp (x)
 (declare (xargs :guard t))
 (let ((__function__ 'functionp))
  (declare (ignorable __function__))
  (and
   (consp x)
   (eq (car x) :function)
   (mbe
     :logic (and (alistp (cdr x))
                 (equal (strip-cars (cdr x))
                        '(name inputs instrs outputs finalize)))
     :exec
     (fty::alist-with-carsp (cdr x)
                            '(name inputs instrs outputs finalize)))
   (b* ((name (cdr (std::da-nth 0 (cdr x))))
        (inputs (cdr (std::da-nth 1 (cdr x))))
        (instrs (cdr (std::da-nth 2 (cdr x))))
        (outputs (cdr (std::da-nth 3 (cdr x))))
        (finalize (cdr (std::da-nth 4 (cdr x)))))
     (and (identifierp name)
          (function-input-listp inputs)
          (instruction-listp instrs)
          (function-output-listp outputs)
          (finalizationp finalize))))))

Theorem: consp-when-functionp

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