[R6RS] Empty `case' and `cond' expressions?

[R. Kent Dybvig]

> > I wouldn't mind, but the situation is not entirely analogous, 
>
> Could you say why?

If I'm building a cond or case via automatic means, I can get the effect
of no clauses by using '([else (if #f #f)]) as the base case rather than
'().  That is, for example:

  (cond [else (if #f #f)])

has the same value and effect as what we're presumably envisioning for

  (cond)

There's no similar thing one can do for case-lambda without possibly
ending up with a different exception being raised.

> > so I don't think we need to do so just for the sake of consistency.
>
> By my mind, it's less for consistency, than for simplification purposes.
> (Jonathan Rees alerted me to this, who wasn't even aware of the
> discussion regarding `case-lambda'.)

As I said, I don't mind allowing (cond) and (case e).  Not allowing them
has always seemed an unnecessary restriction to me, but then so has not
allowing (begin) as an expression

Kent