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Fenv

Fenvp

Recognizer for fenv structures.

Signature
(fenvp x) → *

Definitions and Theorems

Function: fenvp

(defun fenvp (x)
  (declare (xargs :guard t))
  (let ((__function__ 'fenvp))
    (declare (ignorable __function__))
    (and (consp x)
         (eq (car x) :fenv)
         (mbe :logic (and (alistp (cdr x))
                          (equal (strip-cars (cdr x))
                                 '(constants curve)))
              :exec (fty::alist-with-carsp (cdr x)
                                           '(constants curve)))
         (b* ((constants (cdr (std::da-nth 0 (cdr x))))
              (curve (cdr (std::da-nth 1 (cdr x)))))
           (and (const-fenvp constants)
                (curvep curve))))))

Theorem: consp-when-fenvp

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