pub fn race(
core: &Core,
binding: &Arc<dyn ProducerBinding>,
sources: Vec<NodeId>,
) -> Result<NodeId, OperatorFactoryError>Expand description
race(s1, s2, ..., sN) — subscribes to all sources; the first to
emit DATA wins. Subsequent traffic from the winner is forwarded;
losers’ messages are no-ops (per Q4=(b) — losers stay subscribed
but their sink callbacks short-circuit). Saves the dynamic
rewiring cost of explicitly unsubscribing losers.
Empty source list completes immediately. Single source is identity-passthrough.
§Errors
Returns OperatorFactoryError::EmptySources when sources is empty
(R5.7.x — race requires ≥1 source; no-winner-possible rejected).