Re: A case where Ada defaults to unsafe?

[Wes Groleau <wesgroleau@spamcop.net>]

Hyman Rosen wrote:
> 
> Darren New wrote:
> 
> > Hyman Rosen wrote:
> >>So in Ada, one could say 'if a /= 0 and b/a > 3' and fall into a
> >>trap that would not happen in C/C++. Discuss?
> > Or, in C, you could say
> >   if (func_with_side_effects(1) || func_with_side_effects(2)) {...}
> > and also not get the answer you might expect.
> 
> It would be the answer *I* expect :-) In Ada, the answer would be
> indeterminate as well if the order of the side effects mattered.

Personally, I agree with the AQS philosophy: If the order of evaluation
matters, the code should show that.  And if it doesn't matter, then
nothing implying that it does matter should clutter up the code.

Requiring the compiler to do a particular order, even if it doesn't
matter conceptually, is preventing the compiler from optimizing the
order when it affects efficiency.  (And requiring people to use
"and then" all the time also interferes with the optimizer, as well
as adding misleading clutter to the code.)

On the other hand, there's something to be said for determinism.

-- 
Wes Groleau
http://freepages.rootsweb.com/~wgroleau