Collecting information with Readline

promptPerson.js

/*Readline is a module that allows us to ask questions to our Terminal user.
  The standard input(stdin) and standard output(stdout) objects that allow 
 us to easily control prompting a user with questions and saving those answers.
*/

//create an instance of the readline object which will create the propmt.
var readline = require('readline');
var realPerson = { 
  name: '', 
  saying: []
};

//use readline to create the interface that takes in process.stdin & process.stdou
var rl = readline.createInterface(process.stdin, process.stdout);
  // use that answer to set the real person's name
  realPerson.name = answer;
  //in order to ask the question, we need to invoke rl.question
  rl.question('What is the name of a real person', function(answer) {
  // function that we can use to set the Readline prompt
  rl.setPrompt(`What would ${realPerson.name} say? ('exit' to leave)` );
  rl.prompt();     
  /*rl.on('line') is an event that will fire when the user submits an answer
    This callback function, the second argument of the rl.on('line', function() will also be invoked once we have that answer
  */
  rl.on('line', function(saying) {
	   if( saying.toLowercase.trim() === 'exit') {
		   rl.close();
	   } else { 
	   	rl.setPrompt(`What else would ${realPerson.name} say? ('exit' to leave) `)
	   }
		console.log(saying.trim());
	});
});

//rl.on('close') will listen for a close event. 
rl.on('close', function() {
	/*a %s in the console log is a placeholder for a string 
	  So what it will do is it will replace the second argument that we have added with that string.
	  a %j in the console log will replace it variable with a JSON String.
	*/
	console.log('%s is a real persons that says %j', realPerson.name, realPerson.sayings);
	//invoke a process.exit to end the proces 
	process.exit();
});