todo.txt

static inherit from base with most functionality, derived just has data storage rather than janky include impl, or CRTP?
and/or range/container adapter
simd
inc/dec by find first set and find first zero
benchmarks versus other libraries
forget interleave/spread? but expose scatter/gather

bits::bitarray<size, T = size_t> = std::array<T, size>
    copy, move ctors
    everything implemented
bits::bitvector<T = size_t> = std::vector<T>
    performance warning copy operators
bits::bitspan<size = std::dynamic_extent, T = size_t> = std::span<T, size>
    disable copy operators

can they all be implemented on the same underlying type?

they should interoperate
bitarray op bitvector should work
easiest if there's a single underlying type

casts between sizes, storage types?

what if two bitvectors have different dynamic sizes?
zero-extend? one-extend? sign-extend?
make it the users problem:
    error if the sizes differ
virtual zero bits could work?
    assuming ones are important in most cases



https://github.com/ClaasBontus/bitset2

fix test suite
reference type https://en.cppreference.com/w/cpp/utility/bitset/reference
iterators for for loops?

implement casts between bitarray, bitvector, bitspan
    std::bitset is not trivially copyable by the standard, but is in practice (big three std libs), use std::bit_cast to cast from/to it
        see https://quuxplusone.github.io/blog/2019/02/20/p1144-what-types-are-relocatable/
    pretty much like std::array "This container is an aggregate type with the same semantics as a struct holding a C-style array T[N] as its only non-static data member."
implement span_cast and array_cast for conversions