code: function(children) {
  			_assert(
  				children && (!this.children || this.children.length === 0),
  				"only init supported"
  			);
  			this.children = [];
  			for (var i = 0, l = children.length; i < l; i++) {
  				this.children.push(new FancytreeNode(this, children[i]));
  			}
  		}
docs: TODO: activate() TODO: activateSilently() /* Internal helper called in recursive addChildren sequence.