Function Pair

internal/debug/debug.go:151–181

Pair returns the event linked to id, in either direction. If the given event has a CorrelatedID, that's the request it's paired with. Otherwise Pair walks the ring looking for an event whose CorrelatedID equals id — that would be its response. Returns (zero, false) when no link exists or the paired

(id uint64)

// that would be its response. Returns (zero, false) when no link exists or
// the paired event has aged out of the ring.
func Pair(id uint64) (Event, bool) {
	mu.Lock()
	defer mu.Unlock()
	var target Event
	var have bool
	for _, e := range events {
		if e.ID == id {
			target, have = e, true
			break
		}
	}
	if !have {
		return Event{}, false
	}
	if target.CorrelatedID != 0 {
		// Response → walk back to the request.
		for _, e := range events {
			if e.ID == target.CorrelatedID {
				return e, true
			}
		}
		return Event{}, false
	}
	// Request → walk forward to find a response that points back.
	for _, e := range events {
		if e.CorrelatedID == target.ID {
			return e, true
		}
	}
	return Event{}, false
}

// FindByID returns the event with the given monotonic ID, if it's still in
// the ring. Used by /debug show to look up a specific event.