Vinnie Falco wrote:
On Wed, Jun 24, 2026 at 10:21 AM Peter Dimov <pdimov@gmail.com <mailto:pdimov@gmail.com> > wrote:
You need the definitions of const_buffer and mutable_buffer to be available in order to see whether they have constructors from this or that, which requires physical coupling.
If const_buffer was constructible from span<byte> then this is a perfectly valid buffer sequence which does not require physical coupling:
array<const_buffer, 3>
I assume you mean array<span<byte const>, 3> here.
This way we don't need the full strength of an explicit concept, yet we can still get the benefits.
I have no idea what "full strength" there is. A concept is a concept, it's not any more complicated or strong than a concrete type.
A concept is stronger than a concrete type because a concrete type comes in exactly one formulation while types which satisfy a concept comes in infinite formulations.
Right. So the set of types considered buffers is closed, because const_buffer only has a finite set of constructors, which is unlike a concept that can be satisfied by an unbounded set of user-defined types that do not require your explicit constructor-based blessing. And you consider this an argument in favor.