Loops can break with a value - The Edition Guide

# `loop`s can break with a value

`loop`s can now break with a value:

    # #![allow(unused_variables)]
    #fn main() {
    // old code
    let x;

    loop {
        x = 7;
        break;
    }

    // new code
    let x = loop { break 7; };
    #}

Rust has traditionally positioned itself as an “expression oriented language”, that is, most things are expressions that evaluate to a value, rather than statements. `loop` stuck out as strange in this way, as it was previously a statement.

For now, this only applies to `loop`, and not things like `while` or `for`. See the rationale for this decision in RFC issue #1767.