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