# Macro log::warn [−] [src]

    macro_rules! warn {
        (target: $target:expr, $($arg:tt)*) => { ... };
        ($($arg:tt)*) => { ... };
    }

Logs a message at the warn level.

Logging at this level is disabled if any of the following features are present: `max_level_off` or `max_level_error`.

When building in release mode (i.e., without the `debug_assertions` option), logging at this level is also disabled if any of the following features are present: `release_max_level_off` or `max_level_error`.

# Examples

    let warn_description = "Invalid Input";

    warn!("Warning! {}!", warn_description);
    warn!(target: "input_events", "App received warning: {}", warn_description);

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