Get the phase field from a major-frame.
(major-frame->phase x) → phase
This is an ordinary field accessor created by defprod.
Function:
(defun major-frame->phase$inline (x) (declare (xargs :guard (major-frame-p x))) (declare (xargs :guard t)) (let ((__function__ 'major-frame->phase)) (declare (ignorable __function__)) (mbe :logic (b* ((x (and t x))) (acl2::maybe-natp-fix (cdr (std::da-nth 2 x)))) :exec (cdr (std::da-nth 2 x)))))
Theorem:
(defthm maybe-natp-of-major-frame->phase (b* ((phase (major-frame->phase$inline x))) (acl2::maybe-natp phase)) :rule-classes :type-prescription)
Theorem:
(defthm major-frame->phase$inline-of-major-frame-fix-x (equal (major-frame->phase$inline (major-frame-fix x)) (major-frame->phase$inline x)))
Theorem:
(defthm major-frame->phase$inline-major-frame-equiv-congruence-on-x (implies (major-frame-equiv x x-equiv) (equal (major-frame->phase$inline x) (major-frame->phase$inline x-equiv))) :rule-classes :congruence)