On: Zcoin implementation bug enabled attacker to create over 500K Zcoins

[tyingq]

Interesting. Is there any plausible way that Rust can fall into the == vs = trap?

[steveklabnik → tyingq]

No, as assignment always results in (), and if always requires a boolean. This is by design.

[tyingq → steveklabnik]

Ah...so this works:

  fn main() {
      let mut x = false;
      println!("{}", x);
      if {x=true;x} {
          println!("{}", x);
      }
  }

But stands out as pretty obvious. Not something you might easily sneak into a codebase.

[steveklabnik → tyingq]

Sneaky! Yeah, no way this should get past code review, and not even easy to accidentally type.

[aethertap → tyingq]

I haven't yet reached the level of Rust mastery where I'm confident in this answer, but as far as I can tell it's very hard to make that kind of mistake. I'd be very interested to hear what others have to say on it though.