code: function Collection(nodes) {
    this.length = 0;
    if (nodes) {
      nodes = unique(nodes);
      this.length = nodes.length;
      // add each node to an index-based property on collection, in order to
      // appear "array"-like
      for (var i = 0, len = nodes.length; i < len; i++) {
        this[i] = nodes[i];
      }
    }
  }
docs: Creates an instance of `Collection`.
  
  @constructor
  @param {Array} nodes DOM elements to wrap.
  @api protected