brendan at mozilla.org
Mon Feb 12 13:21:31 PST 2007
On Feb 12, 2007, at 12:51 PM, John Cowan wrote:
> Steve Yegge scripsit:
>> Hi folks,
>> A little bird told me that TG1 may have dropped support for the
>> assignment operators &&=, ||=, ^^= due to lack of popular demand
>> compelling use cases.
>> If so, I thought I'd lobby to get at least ||= added back in.
> I agree, and I think there is a use case for &&= as well. Suppose
> that x is either an integer or null. Then
> x &&= x + 5;
> will increment x by 5 unless it is null, in which case it will be
> left alone. (This will not work in languages where 0 is false,
> like C and Perl.)
'' is false in Perl, so this worksforme in Perl:
$x &&= $x + 5;
Is that what you meant?
BTW, I'm in favor of &&= and ||= now that I think for three seconds
about the || use cases I know, which really wanted ||= all along.
One pill that we spat out along with these, perhaps it was the only
poison: ^^ (and ^^= if ^^ is there). Does anyone have a use-case for
value-preserving ^^? We didn't think so when TG1 last considered
these oddments from Waldemar's draft js2/es4 proposals.
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