[eklavya]

In my opinion it's pretty clear. Rust promises memory safety to me, so all code that is safe IS memory safe. I need to mark a block "unsafe" and have an understanding with the compiler that it can't ensure memory safety here and I am on my own. Makes perfect sense to me :)

[robalni]

If we say that "safe" code is "memory-safe" code, now the question is: what is memory-safe code? If memory-safe code is code that doesn't access the memory in unintended ways, then who knows what is unintended? Only the programmer does; it's impossible to write a compiler that knows what the programmer intends.

Like if you only want to access the data inside the bounds of the array, that's one intention that the compiler will help you to check. If you never intend to access the first element in the array, that's an intention that the compiler doesn't help you to check.

So, there is no memory-safe code or language. I think the only way you could define memory-safe code is that memory-safe code can't contain any code that breaks some rules that the compiler checks for. The problem with that is that those rules could be just about anything, so that definition is pretty useless.

[eklavya]

On the contrary, that definition is the whole point and useful if both parties (compiler and programmer) agree what they mean. It's definitely useless for philosophical musings about words and meanings and what not :D

[robalni]

I totally agree; it's useful to have a language feature that enforces some rules that the programmer knows about. It's just useless to call it "safe". My point is just about the words people use when talking about these things :)