Labels

continue と break はオプションでラベル引数を取ることができます。ラベルはネストしたループから抜け出すために使われます。

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Speaker Notes
  • Labeled break also works on arbitrary blocks, e.g. 
    #![allow(unused)]
fn main() {
'label: {
    break 'label;
    println!("This line gets skipped");
}
}