Method subspan

src/fl/stl/span.h:489–494

    // Compile-time sized subspan
    template<fl::size Offset, fl::size Count = dynamic_extent>
    span<T, Count> subspan() const FL_NOEXCEPT {
        if (Count == dynamic_extent) {
            return span<T, Extent - Offset>(mData + Offset, Extent - Offset);
        }
        return span<T, Count>(mData + Offset, Count);
    }

    // Runtime subspan
    span<T, dynamic_extent> subspan(fl::size offset, fl::size count = dynamic_extent) const FL_NOEXCEPT {