Get the phase field from a chase-position.
(chase-position->phase x) → phase
This is an ordinary field accessor created by defprod.
Function:
(defun chase-position->phase$inline (x) (declare (xargs :guard (chase-position-p x))) (declare (xargs :guard t)) (let ((__function__ 'chase-position->phase)) (declare (ignorable __function__)) (mbe :logic (b* ((x (and t x))) (ifix (cdr (std::da-nth 1 x)))) :exec (cdr (std::da-nth 1 x)))))
Theorem:
(defthm integerp-of-chase-position->phase (b* ((phase (chase-position->phase$inline x))) (integerp phase)) :rule-classes :type-prescription)
Theorem:
(defthm chase-position->phase$inline-of-chase-position-fix-x (equal (chase-position->phase$inline (chase-position-fix x)) (chase-position->phase$inline x)))
Theorem:
(defthm chase-position->phase$inline-chase-position-equiv-congruence-on-x (implies (chase-position-equiv x x-equiv) (equal (chase-position->phase$inline x) (chase-position->phase$inline x-equiv))) :rule-classes :congruence)