RangeExtra

[Denis Koroskin]

On Thu, 23 Apr 2009 22:37:37 +0400, Andrei Alexandrescu <SeeWebsiteForEmail at erdani.org> wrote:

> dsimcha wrote:
>> I'm loving the new Phobos, and have been playing around with ranges,  
>> alias
>> this, etc.  I've compiled a list of a few range types that I have at  
>> least
>> partial implementations of for personal use that were overlooked by  
>> Andrei, et
>> al. in the initial release of the new Phobos.  Please tell me which of  
>> these
>> are generally useful and should be cleaned up and released, which ones  
>> are too
>> niche to belong in Phobos, which ones std.range can already do by some
>> slightly non-obvious idiom, and which ones, if any, are already in the  
>> works.
>
> I think these are fantastic. Some comments within.
>
>> CapacityArray:  A range that covers a builtin array and gives it a  
>> capacity
>> field.  All operations that don't have to do with appending are  
>> forwarded to
>> the underlying array via alias this (modulo a few compiler bugs),  
>> meaning that
>> a CapacityArray has an identical compile time interface to a builtin  
>> array,
>> and is implicitly convertible to one.
>
> Upon more thinking, I think we'll have to bit the bullet and define  
> Array!T and Slice!T. Then dmd rewrites:
>
> [ a, b, c ] -> .Array!(typeof(a))(a, b, c)
> T[new] -> .Array!(T)
> new T[n] -> .Array!(T)(n)
> T[] -> .Slice!(T)
>
> It seems increasingly clear that slices alone can't quite cut the  
> mustard.
>
> So your CapacityArray will essentially be the basis of Array.
>

Now that there is a consideration about putting built-in types into a library...

... how about introducing struct MaybeNull(T) { ... } among them (and NonNull-by-default)?

Oh, and Object.d deserves a better name, IMHO.