Yup, I agree with you (and pjmlp, who I can't reply to) on all of this. I can see where you're coming from in pushing for all-value semantics, taking advantage

Yup, I agree with you (and pjmlp, who I can't reply to) on all of this. I can see where you're coming from in pushing for all-value semantics, taking advantage of the mechanisms built into the language to control how those semantics play out. I think it's worth remembering through all of this that getting just the right semantics requires a little more effort and thought on the part of the callee, in C++-land, as well as which the relative lack of consistency (and opaqueness) in these semantics, at least in the absence of a full IDE or similar to jump to signatures. Oh and briefly, the C++ may be unidiomatic, but it's perhaps useful as a C++ mimicry of the Rust code to show maximally similar semantics? I think perhaps the dismissive nature of your GP post blinded me to exactly what standard you wanted the C++ to hold to (oh and also, swapping out heap allocation still seems to be missing the point, as there are definitely cases where that's the 'right' behaviour)