Map#get needs a default value param?

[David Bruant]

Le 12/06/2012 18:02, Tab Atkins Jr. a écrit :
> On Tue, Jun 12, 2012 at 7:36 AM, David Bruant<bruant.d at gmail.com>  wrote:
>> Le 12/06/2012 16:19, Hemanth H.M a écrit :
>>
>> Would it be useful to have something like sum[value] = sum.get(value, 0) + 1
>>
>> You can always do
>>
>>      sum[value] = (sum.get(value) || 0) + 1;
>>
>> I think it's simple enough to justify not having an additional (and
>> potentially confusing) argument, but I'm open to debate.
> The default argument in python's Dict.get doesn't seem confusing, and
> I've used it plenty.  (I've also used the more specialized Dict
> variants that obviate it - Counter and DefaultDict.)
"sum.get(value) || 0" leaves no ambiguity (assuming you know JavaScript 
and falsy values) as to when the value is 0, while for "sum.get(value, 
0)", the implicit part is in the semantics of the function for which you 
need to look at the spec, that's what I find more confusing. YMMV.

David