code: function Prompt() {
    Base.apply(this, arguments);
  
    if (!this.opt.choices) {
      this.throwParamError('choices');
    }
  
    this.validateChoices(this.opt.choices);
  
    // Add the default `help` (/expand) option
    this.opt.choices.push({
      key: 'h',
      name: 'Help, list all options',
      value: 'help'
    });
  
    // Setup the default string (capitalize the default key)
    this.opt.default = this.generateChoicesString(this.opt.choices, this.opt.default);
  
    this.paginator = new Paginator();
  }
docs: Constructor