ISubscriber

ISubscriber defines the minimal interface for any component that consumes events via EventBus. It provides a stable identity for routing.

using SubscriberId = uint64_t;

struct ISubscriber
{
  virtual SubscriberId id() const = 0;
};

Purpose

• Abstract base for all event consumers, enabling uniform routing and identification.

Responsibilities

Method	Description
id()	Returns a globally unique ID for this subscriber.

Notes

• SubscriberId is typically derived from pointer identity or hash — no strong ownership implied.
• Used by EventBus<T> to track subscribers and apply fan-out policy.
• Derived interfaces like IMarketDataSubscriber and IOrderExecutionListener extend this base.