function Manager(uri, opts) {
	  if (!(this instanceof Manager)) return new Manager(uri, opts);
	  if (uri && 'object' === (typeof uri === 'undefined' ? 'undefined' : _typeof(uri))) {
	    opts = uri;
	    uri = undefined;
	  }
	  opts = opts || {};
	
	  opts.path = opts.path || '/socket.io';
	  this.nsps = {};
	  this.subs = [];
	  this.opts = opts;
	  this.reconnection(opts.reconnection !== false);
	  this.reconnectionAttempts(opts.reconnectionAttempts || Infinity);
	  this.reconnectionDelay(opts.reconnectionDelay || 1000);
	  this.reconnectionDelayMax(opts.reconnectionDelayMax || 5000);
	  this.randomizationFactor(opts.randomizationFactor || 0.5);
	  this.backoff = new Backoff({
	    min: this.reconnectionDelay(),
	    max: this.reconnectionDelayMax(),
	    jitter: this.randomizationFactor()
	  });
	  this.timeout(null == opts.timeout ? 20000 : opts.timeout);
	  this.readyState = 'closed';
	  this.uri = uri;
	  this.connecting = [];
	  this.lastPing = null;
	  this.encoding = false;
	  this.packetBuffer = [];
	  var _parser = opts.parser || parser;
	  this.encoder = new _parser.Encoder();
	  this.decoder = new _parser.Decoder();
	  this.autoConnect = opts.autoConnect !== false;
	  if (this.autoConnect) this.open();
	}
`Manager` constructor.

@param {String} engine instance or engine uri/opts
@param {Object} options
@api public