Front page | perl.perl5.porters |
Postings from August 2012
On Tue, Aug 28, 2012 at 2:43 PM, Ricardo Signes
<perl.p5p@rjbs.manxome.org>wrote:
> given ($x) {
> when ($y) { ... } # $x ~~ $y
> when (4) { ... } # $x == 4
> when ('4') { ... } # $x eq 4
> }
>
> Deferred/computed values of any sort mean smart match.
>
> Two dead-simple special cases: Numeric literals mean ==. String literals
> mean
> eq.
>
I agree this solves many of the technical issues raised, but I fear that
it's going to confuse some people or mis-set expectations.
* Currently when() does smartmatch, so you have to retrain people not to
think of when() as smartmatch, but to think of when() as a "smart switch"
or something.
* You can test a value with when() that you can't smartmatch, so if people
don't internalize that when() is no longer smartmatch, at some point
they'll smartmatch a literal and expect it to work like when.
Since smartmatching a literal isn't ambiguous, I think that it would be
less confusing to just add literals to the smartmatch table and let when()
stay as smartmatch. That means *one* big change instead of two.
FWIW, I would still like "when {...} {...}" as a shorter way to write "when
(sub{...}) {...}", but think that's "nice to have" and not necessary for
fixing smartmatch.
David
--
*David Golden* <dagolden@cpan.org>
*Take back your inbox!* → http://www.bunchmail.com/
Twitter/IRC: @xdg
Thread Previous
|
Thread Next