Method subscribe

lib/diagnostics_channel.js:130–136

(subscription)

// TODO(qard): should there be a C++ channel interface?
class ActiveChannel {
  subscribe(subscription) {
    validateFunction(subscription, 'subscription');
    this._subscribers = ArrayPrototypeSlice(this._subscribers);
    ArrayPrototypePush(this._subscribers, subscription);
    channels.incRef(this.name);
    if (this._index !== undefined) subscriberCounts[this._index]++;
  }

  unsubscribe(subscription) {
    const index = ArrayPrototypeIndexOf(this._subscribers, subscription);