[lmm]

> yet the idea that a project no longer actively developed will be rewritten in rust is not?

Rewriting it in Rust while continuing to actively develop the project is a lot more plausible than keeping it in C++ and being able to "maintain a stable codebase" but somehow still fix bugs.

(Keeping it in C++ and continuing active development is plausible, but means the project will continue to have major vulnerabilities)

[bluGill]

I'm not convinced. Rust is nice, but every time I think I should write this new code in Rust I discover it needs to interoperate with some C++ code. How to I work with std::vector<std::string> in rust - it isn't impossible but it isn't easy (and often requires copying data from C++ types to Rust types and back). How do I call a C++ virtual function from Rust?

The above issue is why my code is nearly all C++ - C++ was the best choice we had 15 years ago and mixing languages is hard unless you limit yourself to C (unreasonably simple IMO). D is the only language I'm aware of that has a good C++ interoperability story (I haven't worked with D so I don't know how it works in practice). Rust is really interesting, but it is hard to go from finishing a "hello world" tutorial in Rust to putting Rust in a multi-million line C++ program.

[zozbot234]

Rust/C++ interop is in fact complex and not obviously worthwhile - some of the underlying mechanisms (like the whole deal with "pinned" objects in Rust) are very much being worked on. It's easier to just keep the shared interface to plain C.

[bluGill]

Read I should keep writing C++ code in my project instead of trying to add Rust for new code/features.

I'm not happy with my situation, but I need a good way out. Plain C interfaces are terrible, C++ for all the warts is much better (std::string has a length so no need for strlen all over)

[gpderetta]

The idea is to keep it in C++ and do new development in an hypothetical Safe C++. That would ideally be significantly simpler than interface with rust or rewrite.

There is of course the "small" matter that Safe C++ doesn't exist yet, but Google analysis showing that requiring only new code to be safe is good enough, is a strong reason for developing a Safe C++.

[steveklabnik]

Safe C++ does exist today: it’s implemented in Circle. You can try it out on godbolt right now.

[gpderetta]

Thanks! I have been putting off playing with rust lifetimes. I guess now I have no excuses.