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//! Logging macros that optionally forward to the `log` crate. macro_rules! warn { ($fmt:literal $(, $($arg:expr),* $(,)?)?) => {{ #[cfg(feature = "logging")] { ::log::warn!($fmt $(, $($arg),*)?); } #[cfg(not(feature = "logging"))] { $($(let _ = &$arg;)*)? } }}; }