tail const

[Simen kjaeraas]

Simen kjaeraas <simen.kjaras at gmail.com> wrote:

> Andrei Alexandrescu <SeeWebsiteForEmail at erdani.org> wrote:
>
>> On 12/4/10 12:23 PM, Simen kjaeraas wrote:
>>
>>> To expound further on this, I have created the attached module.
>>> Critique wanted.
>>>
>>
>> Looks promising. A few comments.
>>
>> * For TailXxx you need to handle built-in simple types (int, float...)
>> to return themselves. Also, structs for which hasIndirections returns
>> false also return themselves.
>
> Done.
>
>> * tailconst_t does not obey Phobos' naming convention. I think it's fine
>> to use TailConst in spite of the apparent ambiguity.
>
> It adds some .'s:
>      alias SimpleRange!(.TailConst!T) TailConst;
>      static if ( !is( T == .TailMutable!T ) ) {
>      this( SimpleRange.TailImmutable r ) {
>
> Not sure if this is a problem.
>
>
>> * You may want to add more stringent checks for tailconst_t (well
>> TailConst etc) to make sure it's not bogus - has the same size,
>> compatible members etc.
>
> I've tried, and it seems adding
>        static assert( T.sizeof == T.TailConst.sizeof );
> does not work (no size yet for forward reference).
>
> Checking that all members are the same type and order is easy and
> works. Comparing member names bumped me into bug 5079. Likely related
> to the above, seeing as both have to do with unfinished types.
>
>
>
> I've also considered a template on the form
>
>      mixin tailConst!( SimpleRange, SimpleRange!( Tail!T ) );
> or
>      mixin tailConst!( SimpleRange, Tail!T );
>
> which would automagically define aliases. More work for me, perhaps
> less work for users.
>
> This could not define constructors, as overloads from inside template
> mixins don't work with overloads outside.
>

Nobody ever commented on this. Figured I'd poke around with a stick
and see if there were any opinions. IOW: bump.

-- 
Simen