document issue #255

Author: RobinHankin

man/Ops.hyper2.Rd

@@ -59,6 +59,11 @@ hyper2_sum_numeric(H, r)
   work (without this, one has to type \code{icons["L"] <-
   powers(icons["L"]) + 3}, which sucks).
 
+  Currently, this operation returns an error if the powers have length
+  exceeding one, so \dQuote{\code{icons[list("NB","L")] + 5}} fails.  In
+  the future, I might return a \code{disord} object instead [so errors
+  would be flagged as \CRANpkg{disordR} discipline violations].
+
   Raising a \code{hyper2} object to a power returns an error.  There are
   no unary operations for this class.
 }