Re: Does this make sense?

--5 is equivalent to -(-5).  There was a previous thread about the
precise meaning of unary minus: check the archive.  It does what you
would expect.

gmarcy@us.ibm.com wrote:
> 
> The production for
> 
> [27] UnaryExpr ::= UnionExpr  | '-' UnaryExpr
> 
> seems to imply that --5 (or -----5 for that matter) are UnaryExprs.  Since
> the
> spec seems to be a little light on defining what "negation" means, and the
> wording seems to always be something like "preceded by a minus sign"
> and "an optional minus sign", does this seem like something worth bringing
> up as an issue?  Is the behavior the obvious (or not ::smile::) repeated
> application of negation, i.e. even occurrences of minus signs cancel each
> other out?
> 
> Glenn Marcy
> Technical Consultant
> XML Technology Group, IBM

Received on Monday, 27 March 2000 01:12:22 UTC