2 ms·

They probably meant it is a race, not racy. Although, it's not a race I think? The method will attempt to reserve, or return Err, just like malloc would (it's n

• iudqnolq 6y ago
  I think they're referring to something like this let v = vec![0; 42]; v.try_reserve(1); frob(&mut v); // I expect this not to expand the array v.push(1); // fails, because frob took the space Note that this requires passing a mutable reference to frob. Absent an explicit contract in the api documentation I wouldn't expect a function that takes a mutable reference to a vec not to mutate it arbitrarily. One option for avoiding this would be to pass a mutable reference to a slice, which allows frob to mutate elements of the vec without allowing it to push. frob(&v[..]) It can't be a race in the traditional sense, as the borrow checker will enforce only one person being able to write at a time.
  • Ericson2314 6y ago
    Yes exactly. Thanks.