code: function UI(options) {
    if (!(this instanceof UI)) {
      var ui = Object.create(UI.prototype);
      UI.apply(ui, arguments);
      return ui;
    }
    debug('initializing from <%s>', __filename);
    this.options = utils.createOptions(options);
    this.appendedLines = 0;
    this.height = 0;
    this.initInterface();
  }
docs: Create a readline interface to use in prompts