On Wednesday, 3 October 2018 at 08:21:38 UTC, Manu wrote:
Okay, so copy elision is working... but moves otherwise are not? That's still not what we've been peddling all these years. A whole lot of design surface area is dedicated to implicit move semantics... and they don't work? What does it do? postblit unnecessarily?
No. The problem is that the language is under-specified. It is built on the *assumption* that no one ever should create self-referencing data. But it does not enforce that. Which eventually leads to someone trying to make such data and then run into a wall, or worse, a heisenbug.
Thing is, there isn't anything wrong with self-referencing data per se. It's that the language plumbing should either disallow it wholesale (i.e. Rust) or allow a graceful way of handling it. Neither is present in D. The latter could be added though, that's what the DIP is about.
