[R6RS] early arity check

[R. Kent Dybvig]

During our meeting on the 7th, Will mentioned that the exception system
requires an early arity check.  Is the following from the
with-exception-handler description the offending text?

  \domain{\var{Handler} must be a
  procedure that accepts one argument.}  The {\cf
  with-exception-handler} procedure returns the result(s) of invoking
  \var{thunk}.  \var{Handler} is installed as the current
  exception handler for the dynamic extent (as determined by {\tt
    dynamic-wind}) of the invocation of \var{thunk}.
  
  \implresp The implementation must check the restrictions on
  \var{handler} to the extent performed by applying it as described,
  when it is called as a result of a call to {\cf raise} or {\cf
    raise-continuable}.

I didn't find any other likely candidates, but it's possible that I'm
looking in the wrong place.  It's not clear to me, however, that this does
require an early arity check.

Kent