On Fri, 20 Aug 2004, Larry Wall wrote:
> On Fri, Aug 20, 2004 at 10:07:02PM +0200, Juerd wrote:
> : I'm proposing
> :
> : for zip(@foos, @bars, @xyzzies) <-> $foo, $bar, $xyzzy { ... }
> : for %quux.kv <-> $key, $value { ... }
>
> That'd probably work on the keys only if the hash was declared to have
> object keys. At least in Perl 5, the key is always a copy.
>
> : to mean
> :
> : for zip(@foos, @bars, @xyzzies) -> $foo is rw, $bar is rw, $xyzzy is rw { ... }
> : for %quux.kv -> $key is rw, $value is rw { ... }
> :
> : Comments, anyone?
>
> It's really sick, and cute, and I love it. Unfortunately I'm not sure
> it passes the "Are there already too many ways to declare a sub?" test...
>
> It's vaguely possible I could be persuaded on the basis that
>
> for zip @a ¥ @b <-> { ($^a,$^b) = ($^b,$^a) }
>
> could be made to work. But I'm still dubious. And arguably -> {...}
> means the same as sub () {...}, implying there are no arguments.
Arguably it already means that. But if <-> were added, it might be a good
reason to make -> {...} mean -> $_ {...}, using <-> {...} for -> $_ is rw
{...}. A good way to remove one more special case (maybe offsetting the extra
way to declare a sub, and sweeten the whole deal).
--
Adam Lopresto
http://cec.wustl.edu/~adam/
Yesterday upon the stair
I met a man who wasn't there.
He wasn't there again today --
I think he's from the CIA.
