[Bug 4271] [FS} Type checking () op Arg

http://www.w3.org/Bugs/Public/show_bug.cgi?id=4271





------- Comment #5 from jmdyck@ibiblio.org  2007-02-27 10:26 -------
(In reply to comment #0)
> ... the typing rules in "C.2 Mapping of
> Overloaded Internal Functions" should be extended to cover this case. 
> Specifically, they do not cover the case of binary operators when one of the
> arguments is the empty sequence and the other has a type not ordinarily
> supported by that operator.

It seems to me that they *do* cover this case. Specifically, in C.2 / STA, the
2nd and 3rd rules allow you to conclude that the expression's type is empty if
either operand's type is empty, regardless of the other operand's type.