Get the prefix field from a bin-expo.
(bin-expo->prefix x) → prefix
This is an ordinary field accessor created by fty::defprod.
Function:
(defun bin-expo->prefix$inline (x) (declare (xargs :guard (bin-expop x))) (declare (xargs :guard t)) (let ((__function__ 'bin-expo->prefix)) (declare (ignorable __function__)) (mbe :logic (b* ((x (and t x))) (bin-expo-prefix-fix (cdr (std::da-nth 0 x)))) :exec (cdr (std::da-nth 0 x)))))
Theorem:
(defthm bin-expo-prefixp-of-bin-expo->prefix (b* ((prefix (bin-expo->prefix$inline x))) (bin-expo-prefixp prefix)) :rule-classes :rewrite)
Theorem:
(defthm bin-expo->prefix$inline-of-bin-expo-fix-x (equal (bin-expo->prefix$inline (bin-expo-fix x)) (bin-expo->prefix$inline x)))
Theorem:
(defthm bin-expo->prefix$inline-bin-expo-equiv-congruence-on-x (implies (bin-expo-equiv x x-equiv) (equal (bin-expo->prefix$inline x) (bin-expo->prefix$inline x-equiv))) :rule-classes :congruence)