Get the prefix field from a dexpo.
(dexpo->prefix x) → prefix
This is an ordinary field accessor created by fty::defprod.
Function:
(defun dexpo->prefix$inline (x) (declare (xargs :guard (dexpop x))) (declare (xargs :guard t)) (mbe :logic (b* ((x (and t x))) (dexprefix-fix (car x))) :exec (car x)))
Theorem:
(defthm dexprefixp-of-dexpo->prefix (b* ((prefix (dexpo->prefix$inline x))) (dexprefixp prefix)) :rule-classes :rewrite)
Theorem:
(defthm dexpo->prefix$inline-of-dexpo-fix-x (equal (dexpo->prefix$inline (dexpo-fix x)) (dexpo->prefix$inline x)))
Theorem:
(defthm dexpo->prefix$inline-dexpo-equiv-congruence-on-x (implies (dexpo-equiv x x-equiv) (equal (dexpo->prefix$inline x) (dexpo->prefix$inline x-equiv))) :rule-classes :congruence)