[boost] Is there a design reason why beast static_string uses size_t for length?

Internally as a member, not talking about template argument. I would naively assume that performance overhead of having conversion from uint8_t/uint16_t(and uint32_t if you want to allow "insanely" large static_strings) to size_t is not big enough to justify "large"(in context of microoptimizations for space) overhead due to alignment and size requirements of size_t(on 64b machines). Recently I other context I complained that there is no way to nicely embed godbolt/source examples in here :), so here is a link with example: https://godbolt.org/z/Y4Y5zKj86 regards, Ivan