owning-ref-rs VS Bronze

Increasingly feeling that Rust is like Elm: a language with novel ideas, teaching valuable lessons (a vocabulary for teaching and checking thread safety, documenting exclusive vs. shared mutability in the type system, arguably a vocabulary for teaching and checking memory safety, though that comes at a steep cost), yet so stubborn the community treats its values (avoiding shared mutability) as moral judgments of code, and the language and deliberately obstructs writing code outside of approved patterns (single ownership tree, exclusive mutability). struct{Cell...}& doesn't need to be harder to use than C++ struct{T...}*, but Rust keeps it difficult because the community views it as bad code design and wants to keep it hard. And *mut T lacks RAII unlike C++'s unique_ptr, and requires unsafe blocks in every dereference. As a result, people turn to unsound patterns like https://github.com/kimundi/owning-ref-rs, https://github.com/mcoblenz/Bronze/, and https://github.com/emu-rs/snes-apu/blob/master/src/smp.rs#L5....

It's a good language to learn. I hesitate to consider it a replacement for asm/C/C++. Writing rust is hoping that the code you're porting to rust can adapt well to the restrictions, and if not, searching for esoteric and needlessly unsafe/verbose workarounds.

Note that there are other soundness issues that require more fundamental changes to be fixed.

That's a shame. I dug into owning_ref, and it looks like it has an open soundness bug as well.

Increasingly feeling that Rust is like Elm: a language with novel ideas, teaching valuable lessons (a vocabulary for teaching and checking thread safety, documenting exclusive vs. shared mutability in the type system, arguably a vocabulary for teaching and checking memory safety, though that comes at a steep cost), yet so stubborn the community treats its values (avoiding shared mutability) as moral judgments of code, and the language and deliberately obstructs writing code outside of approved patterns (single ownership tree, exclusive mutability). struct{Cell...}& doesn't need to be harder to use than C++ struct{T...}*, but Rust keeps it difficult because the community views it as bad code design and wants to keep it hard. And *mut T lacks RAII unlike C++'s unique_ptr, and requires unsafe blocks in every dereference. As a result, people turn to unsound patterns like https://github.com/kimundi/owning-ref-rs, https://github.com/mcoblenz/Bronze/, and https://github.com/emu-rs/snes-apu/blob/master/src/smp.rs#L5....

It's a good language to learn. I hesitate to consider it a replacement for asm/C/C++. Writing rust is hoping that the code you're porting to rust can adapt well to the restrictions, and if not, searching for esoteric and needlessly unsafe/verbose workarounds.

Except the argument is right. Rust makes certain patterns (shared mutability in console emulators, dynamic lifetimes in Wayland) tricky to wrap with a safe abstraction, tedious to access with an unsafe abstraction (unsafe blocks, Arc cloning and raw pointer methods or RefCell borrows or Cell get/set, everywhere), and easy but wrong to wrap with an unsound abstraction (again) which can produce aliased &mut. Meanwhile in C++, pointer aliasing and manual memory lifetime management is both legal and ergonomic, and no more dangerous than unsafe Rust code.

It's not about the internals of the GC. It's about the API that it exposes to users.

The author has some ideas: https://github.com/mcoblenz/Bronze/issues/2#issuecomment-939...

However, in fact-checking myself, I discovered a wrinkle: Bronze's GC doesn't actually do this, and is thus unsound. And someone has already filed an issue on their GitHub repo: https://github.com/mcoblenz/Bronze/issues/2