while

A while loop uses the while keyword followed by a condition which evaluates to a Boolean.

    let mut counter = 0;
    let mut condition = true;
    while counter < 10 && condition {
        counter += 1;
        if 5 < counter {
            condition = false;
        }
    }

In the example above we use two conditions.

1. If the counter is less than 10 then continue to iterate
2. If the condition variable is true then continue to iterate

As long as both those conditions are true then the loop will iterate. In this case the loop will finish iterating once counter reaches the value of 6 because condition will be set to false.

Nested loops

Sway also allows nested while loops.

    while true {
        // computation here
        while true {
            // more computation here
        }
    }