old_contents: /**
   * `confirm` type prompt
   */
  
  var _ = require("lodash");
  var util = require("util");
  var chalk = require("chalk");
  var Base = require("./base");
  var utils = require("../utils/utils");
  var observe = require("../utils/events");
  
  
  /**
   * Module exports
   */
  
  module.exports = Prompt;
  
  
  /**
   * Constructor
   */
  
  function Prompt() {
    Base.apply( this, arguments );
  
    var rawDefault = true;
  
    _.extend( this.opt, {
      filter: function( input ) {
        var value = rawDefault;
        if ( input != null && input !== "" ) {
          value = /^y(es)?/i.test(input);
        }
        return value;
      }.bind(this)
    });
  
    if ( _.isBoolean(this.opt.default) ) {
      rawDefault = this.opt.default;
    }
  
    this.opt.default = rawDefault ? "Y/n" : "y/N";
  
    return this;
  }
  util.inherits( Prompt, Base );
  
  
  /**
   * Start the Inquiry session
   * @param  {Function} cb   Callback when prompt is done
   * @return {this}
   */
  
  Prompt.prototype._run = function( cb ) {
    this.done = cb;
  
    // Once user confirm (enter key)
    var events = observe(this.rl);
    events.line.take(1).forEach( this.onEnd.bind(this) );
  
    events.keypress.forEach( this.onKeypress.bind(this) );
  
    // Init
    this.render();
  
    return this;
  };
  
  
  /**
   * Render the prompt to screen
   * @return {Prompt} self
   */
  
  Prompt.prototype.render = function() {
    var message = this.getQuestion();
    utils.writeMessage( this, message );
  
    return this;
  };
  
  /**
   * When user press `enter` key
   */
  
  Prompt.prototype.onEnd = function( input ) {
    this.status = "answered";
  
    var output = this.opt.filter( input );
  
    this.clean(1).render();
    this.write( chalk.cyan(output ? "Yes" : "No") + "\n" );
  
    this.done( input ); // send "input" because the master class will refilter
  };
  
  /**
   * When user press a key
   */
  
  Prompt.prototype.onKeypress = function() {
      this.clean().render().write( this.rl.line );
  };
new_contents: /**
   * `confirm` type prompt
   */
  
  var _ = require("lodash");
  var util = require("util");
  var chalk = require("chalk");
  var Base = require("./base");
  var utils = require("../utils/utils");
  var observe = require("../utils/events");
  
  
  /**
   * Module exports
   */
  
  module.exports = Prompt;
  
  
  /**
   * Constructor
   */
  
  function Prompt() {
    Base.apply( this, arguments );
  
    var rawDefault = true;
  
    _.extend( this.opt, {
      filter: function( input ) {
        var value = rawDefault;
        if ( input != null && input !== "" ) {
          value = /^y(es)?/i.test(input);
        }
        return value;
      }.bind(this)
    });
  
    if ( _.isBoolean(this.opt.default) ) {
      rawDefault = this.opt.default;
    }
  
    this.opt.default = rawDefault ? "Y/n" : "y/N";
  
    return this;
  }
  util.inherits( Prompt, Base );
  
  
  /**
   * Start the Inquiry session
   * @param  {Function} cb   Callback when prompt is done
   * @return {this}
   */
  
  Prompt.prototype._run = function( cb ) {
    this.done = cb;
  
    // Once user confirm (enter key)
    var events = observe(this.rl);
    events.keypress.takeUntil( events.line ).forEach( this.onKeypress.bind(this) );
  
    events.line.take(1).forEach( this.onEnd.bind(this) );
  
    // Init
    this.render();
  
    return this;
  };
  
  
  /**
   * Render the prompt to screen
   * @return {Prompt} self
   */
  
  Prompt.prototype.render = function() {
    var message = this.getQuestion();
    utils.writeMessage( this, message );
  
    return this;
  };
  
  /**
   * When user press `enter` key
   */
  
  Prompt.prototype.onEnd = function( input ) {
    this.status = "answered";
  
    var output = this.opt.filter( input );
  
    this.clean(1).render();
    this.write( chalk.cyan(output ? "Yes" : "No") + "\n" );
  
    this.done( input ); // send "input" because the master class will refilter
  };
  
  /**
   * When user press a key
   */
  
  Prompt.prototype.onKeypress = function() {
      this.clean().render().write( this.rl.line );
  };
  
subject: Add takeUtil to keypress event