Loop

loop is the simplest loop: it repeats its body forever until something stops it. Use break to exit and continue to skip to the next iteration.

loop {
    if done() {
        break;     // leave the loop
    } else {
        continue;  // jump straight to the next pass
    }
}

Loops are expressions

A loop evaluates to whatever value you break with. This makes it a clean way to “retry until you get a result”:

let answer: int = loop {
    let guess = next_guess();
    if is_valid(guess) {
        break guess; // the loop evaluates to this
    }
};

The result type depends on how the loop ends:

```admonish note title=“break value is for loop only” Plain loop is the one form guaranteed to run, so it can hand back a T directly. while and for might never enter their body, so a value they break out becomes a T? instead — see those pages.