Case Range Statement ..

[Bill Baxter]

On Wed, Jul 8, 2009 at 4:12 PM, Andrei
Alexandrescu<SeeWebsiteForEmail at erdani.org> wrote:
> Jérôme M. Berger wrote:
>>
>>    So, the correct way to define an inclusive range is with "+1" except
>> when it's with "nextUp", unless you're talking about the right end of the
>> range where it is inclusive by default and the right way to make it
>> exclusive is with "+1" except when it's with "nextUp"?
>>
>>    That's what I call consistent!
>
> I completely disagree with your assessment. First, you didn't mention
> what the range is supposed to do. For example, what primitives should
> the range have? Are you talking about a built-in type or a
> library-defined type? etc.
>
> There are two places in the language where expression1..expression2
> comes into play: when slicing an array, and when iterating with foreach.
> In both cases the range is discrete with step 1, and so it makes sense
> to discuss that when expression1..expression2 is being talked about. Now
> you can't just silently redefine what you mean by range and then claim
> inconsistency.
>
> If you want to make a case, please state clearly what are you talking
> about. Nobody can be consistent with a definition that doesn't exist.

I think what Jerome is getting at is that we could be getting more
mileage out of the xpr1..xpr2 syntax.  It would be useful syntax for
more than just integral, dense ranges in foreach and slices.  The
equivalents I've used or seen in Ruby, Python and Matlab are more
versatile than D's.  Perhaps that can't be translated in any useful
way to a static language like D, I dunno.  But it leaves one with the
feeling that D's slice literals are underpowered and that the case
range thing is just plugging a hole in a dilapidated boat rather than
building us a nice new sleek yacht.

--bb