Re: BitArray Slicing

[Ilya Yaroshenko via Digitalmars-d-learn]

On Wednesday, 21 December 2016 at 09:08:51 UTC, Ezneh wrote:
Hi, in one of my projects I have to get a slice from a BitArray.
I am trying to achieve that like this :

void foo(BitArray ba)
{
   auto slice = ba[0..3]; // Assuming it has more than 4 
elements
}

The problem is that I get an error :

"no operator [] overload for type BitArray".

Is there any other way to get a slice from a BitArray ?

Thanks,
Ezneh.

Mir allows you to define simple alternative to BitArray:

https://github.com/libmir/mir

------
struct BitMap
{
    size_t* ptr;

    import core.bitop;

    bool opIndex(size_t index) const
    {
        return bt(ptr, index) != 0;
    }

    void opIndexAssign(bool val, size_t index)
    {
        if(val)
            bts(ptr, index);
        else
            btr(ptr, index);
    }
}

import mir.ndslice;

void main()
{
    auto arr = new size_t[3];
    auto sl = BitMap(arr.ptr).sliced(size_t.sizeof * 8 * 
arr.length);

    sl[4] = true;
    sl[100] = true;
    sl.popFrontN(3);
    assert(sl[1]);
    assert(sl[97]);

    auto sl2 = sl[1...3]; // slicing
}
------