(named-readtables:defreadtable noffi-syntax
  (:merge :standard)
  (:macro-char #\_ (lambda (stream char) (read-hash-underscore stream char nil)) t))

(named-readtables:defreadtable noffi-syntax*
  (:merge :standard)
  (:dispatch-macro-char #\# #\_ #'read-hash-underscore))