> whereas with std::span you get more of a hint what's going on just based on the type You don’t if it’s a span of bytes (or equivalent). Encoding the length

> whereas with std::span you get more of a hint what's going on just based on the type You don’t if it’s a span of bytes (or equivalent). Encoding the length in a span is a meaningful thing. But the fact that it holds a random memory pointer labeled “byte” instead of “void” doesn’t change anything.