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