node-cli.js

var questions = [
  { id:'fname', text:'First Name', answerType:'str' },
  { id:'lname', text:'Last Name', answerType:'str' },
  { id:'age', text:'Age', answerType:'int' },
  { id:'weight', text:'Weight', answerType:'float' }
]

function ask(question, callback) {
  var stdin = process.stdin, stdout = process.stdout;

  stdin.resume();
  stdout.write(question + ": ");

  stdin.once('data', function(data) {
    data = data.toString().trim();
    callback(data);
  });
}

function process_answers(answers) {
  console.log(answers);
}

function main() {
  var i=0, l=questions.length, answers={};

  var process_val = function (val) {
    if(question.answerType == 'int') {
      answers[question.id] = parseInt(val, 10);
    } else if(question.answerType == 'float') {
      answers[question.id] = parseFloat(val);
    } else {
      answers[question.id] = val;
    }
    if(i<l-1) {
      question = questions[++i];
      ask(question.text, process_val);
    } else {
      process_answers(answers)
    }
  };

  var question = questions[i];
  ask(question.text, process_val);
}

main();