This also renames `MutableArrayRef` to `MutableSpan`. The name "Span" works better, because `std::span` will provide similar functionality in C++20. Furthermore, a shorter, more concise name for a common data structure is nice.
This also renames `MutableArrayRef` to `MutableSpan`. The name "Span" works better, because `std::span` will provide similar functionality in C++20. Furthermore, a shorter, more concise name for a common data structure is nice.