BREAK_WITH_LABEL_AND_LOOP in rustc_lint::builtin - Rust
Description: The `break_with_label_and_loop` lint detects labeled `break` expressions with an unlabeled loop as their value expression.

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## BREAK_WITH_LABEL_AND_LOOP

# Static BREAK_WITH_LABEL_AND_LOOP

Source

    pub static BREAK_WITH_LABEL_AND_LOOP: &'static Lint

Expand description

The `break_with_label_and_loop` lint detects labeled `break` expressions with an unlabeled loop as their value expression.

#### §Example

    'label: loop {
        break 'label loop { break 42; };
    };

{{produces}}

#### §Explanation

In Rust, loops can have a label, and `break` expressions can refer to that label to break out of specific loops (and not necessarily the innermost one). `break` expressions can also carry a value expression, which can be another loop. A labeled `break` with an unlabeled loop as its value expression is easy to confuse with an unlabeled break with a labeled loop and is thus discouraged (but allowed for compatibility); use parentheses around the loop expression to silence this warning. Unlabeled `break` expressions with labeled loops yield a hard error, which can also be silenced by wrapping the expression in parentheses.