BitArray - preview of what's to come?

[Dmitry Olshansky]

On 30.05.2012 15:04, Era Scarecrow wrote:
[snip]
>
> Other features: Slice operations available, so you can slice specific
> sets of bits. Since opDollar doesn't work right I can't rely on them
> just yet. uses and accepts ulong for the slices and opIndex. The
> BitArray footprint is about 36 bytes for 32bit systems, and likely
> 40bytes for 64bit systems.

It all went nice and well...
Ouch why 36 bytes?

>
> bool[4] x = [1, 1, 0, 0];
> BitArray ba = BitArray(x);
>
> ba = ba[2 .. ba.length]; //or BitArray(x, 2, x.length)
> assert(ba == x[2 .. $]);
>
>
> // const
>
> ba = BitArray(x);
> const BitArray cba = ba;
> assert(cba == ba);
>
> const BitArray slice = ba[2 .. ba.length]; //slices work too!
> assert(ba[2 .. cba.length] == cba);
> ba[0 .. 2] = cba[];
>
>
> // compact / GC-less.
>
> assert(ba.isCompact()); //if it's true, no GC involved.
> BitArray ca = ba;
> ca[0] = 0;
> assert(ca != ba);
>
> ba.length = 1000;
> assert(!ba.isCompact()); //GC'd
> ba = ba[0 .. 4];
> assert(!ba.isCompact()); //slice doesn't automatically convert to compact
>
> ca = ba;
> ca[0] = 0;
> assert(ba == ca); //like a regular slice, shares memory

Cool.

-- 
Dmitry Olshansky