FGL binder that checks whether X is syntactically known true.
(check-true ans x) → *
See fgl-syntactic-checker-binders and see binder for details.
Function:
(defun check-true (ans x) (declare (xargs :guard t)) (let ((__function__ 'check-true)) (declare (ignorable __function__)) (and x ans t)))
Theorem:
(defthm check-true-implies-true (implies (check-true ans x) x) :rule-classes :forward-chaining)
Theorem:
(defthm iff-implies-equal-check-true-2 (implies (iff x x-equiv) (equal (check-true ans x) (check-true ans x-equiv))) :rule-classes (:congruence))