Larry Wall <[EMAIL PROTECTED]> writes:
> On Thu, Oct 16, 2008 at 10:37:41PM +0200, Eirik Berg Hanssen wrote:
> : [EMAIL PROTECTED] writes:
> :
> : > -C<< infix:<where> >>, sequential junctional and operator
> : > +C<< infix:<also> >>, sequential junctional and operator
> : >
> : > - EXPR where EXPR where EXPR ...
> : > + EXPR also EXPR also EXPR ...
> : >
> : > Can be used to construct ANDed patterns with the same semantics as
> : > C<< infix:<&> >>, but with left-to-right evaluation guaranteed, for use
> : > in guarded patterns:
> : >
> : > - $target ~~ MyType where .mytest1 where .mytest2
> : > + $target ~~ MyType also .mytest1 also .mytest2
> : >
> : > This is useful when later tests might throw exceptions if earlier
> : > tests don't pass. This cannot be guaranteed by:
> :
> : All this, just to get the exceptions in the right order?
>
> It's to get exceptions not to happen at all. Normal junctions don't
> trap exceptions either, but also can't guarantee order of evaluation.
> This variant does. That's all.
Okay, I may be particularly slow this week, but shouldn't that be
specced as "short-curcuit" rather than merely "sequential" and "with
left-to-right evaluation guaranteed"?
(I don't see how you can get exceptions not to happen at all, unless
it's short-circuiting.)
Eirik
--
"Minimal collateral damage" and "entire star system"
do *not* belong in the same sentence.
-- Howard Tayler, http://www.schlockmercenary.com/d/20050326.html
