Macro log_warn 

macro_rules! log_warn {
    ($logger:expr, $($arg:tt)+) => { ... };
}

Emit at crate::Severity::Warn.

rclrs::log_warn!’s spelling — see the module note on RFC-0089’s “each language follows its own upstream” rule. The pre-rename nros_warn! forwarder was removed in phase-417 W-B5.