BitArray/BitFields - Review

[Jonathan M Davis]

On Sunday, July 29, 2012 00:58:59 Dmitry Olshansky wrote:
> My solution is make slices different type e.g. BitSlice.
> It's always reference to the original BitArray. Array itself still can
> be either compact or not. All operations with slice go to array (and
> still check if they can use word-aligned speed up).
> 
> How does it sound?

I would point out that while hasSlicing doesn't currently check for it, if 
opSlice doesn't return a type which is assignable to the original range, it 
won't work in a lot of Phobos functions. I keep meaning to bring that up for 
discussion in the main newsgroup. I'd argue that hasSlicing really be changed 
from

    enum bool hasSlicing = !isNarrowString!R && is(typeof(
    (inout int _dummy=0)
    {
        R r = void;
        auto s = r[1 .. 2];
        static assert(isInputRange!(typeof(s)));
    }));

to something like

    enum bool hasSlicing = !isNarrowString!R && is(typeof(
    (inout int _dummy=0)
    {
        R r = void;
        auto s = r[1 .. 2];
        static assert(isInputRange!(typeof(s)));
        r = s;
    }));

- Jonathan M Davis