It's absolutely different: “I call it my billion-dollar mistake. It was the invention of the null reference in 1965. At that time, I was designing the first comprehensive type system for references in an object oriented language (ALGOL W). My goal was to ensure that all use of references should be absolutely safe, with checking performed automatically by the compiler. But I couldn't resist the temptation to put in a null reference, simply because it was so easy to implement. This has led to innumerable errors, vulnerabilities, and system crashes, which have probably caused a billion dollars of pain and damage in the last forty years.”
replyHis mistake was making _all_ reference taking functions also accept null. In Rust functions opt into None | Some
This comes up with C# which must have default(T) so references default to null. In Rust there is no general default(T) that must always resolve
My contrast was to "That feels quite a bit different". The type system in C only has Tony's nullable references, you can't say that you don't mean that because it wasn't your choice to make, it's like if some C programmers say obviously they don't mean zero when they take an integer - too bad, C doesn't have the non-zero integers (Rust does, NonZeroI32 for example is the signed 32-bit integers except zero)
replyIt is different. Handling `None` in a way that crashes your program is well defined in a Rust function. If you're using `unwrap` or `expect`, the program will crash with a stack trace and an error, instead of running into undefined behavior.
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