Immutable static arrays

[Daniel Murphy]

"H. S. Teoh" <hsteoh at quickfur.ath.cx> wrote in message 
news:mailman.805.1331958621.4860.digitalmars-d at puremagic.com...
> On Sat, Mar 17, 2012 at 02:59:55PM +1100, Daniel Murphy wrote:
> [...]
>> > So there's no tail-const type for static arrays?
>> >
>> > More to the point, how should AA's with immutable static array keys
>> > be implemented? The current implementation doesn't work at all
>> > because the input static array can't be assigned to the Slot (the
>> > static array field in Slot is completely immutable, even from the
>> > Slot ctor???).
> [...]
>> This is correct.  It's the same as for primitive types.  Because they
>> implicitly convert to immutable, AAs should store a mutable copy.
>> T[N] should be handled almost the same as T.
> [...]
>
> So string[immutable int[4]] should store int[4] as key?
>
> I guess I just found it strange that assigning to a string
> (==immutable(char)[]) field is OK, but assigning to immutable(char[4])
> is not.
>

The difference is dynamic arrays contain an indirection, static arrays 
don't.  Treat them the same as you do primitive types and they should work. 
(apart from compiler bugs)