[simias]

Yes the rule is that it defaults to i32 only if there's absolutely no way to infer the exact type by use like in your example. So in practice it almost never happens because as soon as you use the value in an operation or function call the compiler knows the exact type. One exception would be code like:

    fn main() {
        for i in 0..10 {
            println!("{}", i);
        }
    }

Here there's no way for the compiler to know what exact integer type is expected so it defaults to i32. There was a debate about this, I was personally in opposition but in my experience it mostly occurs on small "hello world" examples and code snippets so it doesn't really matter. I've never encountered any issues stemming from this rule so far. At least they got rid of the "int" and "uint" types which is a great thing in my opinion.