Primitive E module for a delayed assignment.
We use this to implement vl2014::*vl-1-bit-delay-1*. However, really esim has no concept of delays and this is no different *esim-id*.
Definition:
(defconst *esim-del* '(:n *esim-del* :x (:out ((|out| . |in|))) :i ((|in|)) :o ((|out|))))