Recognizer for modinst structures.
(modinst-p x) → *
Function:
(defun modinst-p (x) (declare (xargs :guard t)) (let ((__function__ 'modinst-p)) (declare (ignorable __function__)) (and (std::prod-consp x) (b* ((instname (std::prod-car x)) (modname (std::prod-cdr x))) (and (name-p instname) (modname-p modname))))))