JavaScript Test

General.markdown

General

• What JS libraries have you used?
  • Why that over X?
• What JS tempting libraries have you used?
• How do you organize your code?
• Have you used CoffeeScript?
  • What do you like/dislike about it?
  • Advantages/Disadvantages over JavaScript?

What is:

• primitive types
• this
• apply & call
  • What is the difference between the two?
• closures
• lambdas
• JSON

Describe the differences between:

• Loops
  • for
  • for in
  • while
  • forEach
    • is there an issue with for/while that forEach can solve?
  • map
  • reduce
• Variables
  • undefined
  • undeclared
  • null
• Host objects and Native objects.
• Passed by reference vs passed by value
  • Bonus if knows everything is passed by reference but primitives are immutable.

Explain:

• How are variables scoped in JavaScript?
• What is hoisting?
• The prototype chain

Solve:

• FizzBuzz
• Reverse a string
• Reverse the letters but not the word order.
  • Example: "Hello World" becomes "olleH dlroW"
• Flatten a list.
  • Example: [[1], 2, [[3,4], 5], [[[]]], [[[6]]], 7, 8, []] becomes [1, 2, 3, 4, 5, 6, 7, 8]
• Memorize function

harder.js

function hello(what) {
  what = "world";
  return "Hello, " + arguments[0] + "!";

console.log( hello('Chris') );

//
//
//

function allNames() {
  var names = [ 'Chris', 'Skip', 'Jeff' ];
  for (name in names) {
    console.log(name);
  }
}

allNames();
console.log(name);

scope.markdown

(function() {
  var count = 10;

  while (count--) {
    console.log(count);
  }

  console.log(count);
})();

---

(function() {
  var count = 10;

  while (count--) {
    var foo = 'boo';
    console.log(foo);
  }

  console.log(foo);
})();

---

(function() {
  var count = 10;

  (function() {
    while (count--) {
      console.log(count);
    }
  })();

  console.log(count);
})();

---

(function() {
  var count = 10;

  (function() {
    var count = 5;
 
    while (count--) {
      console.log(count);
    }
  })();

  console.log(count);
})();

typeof.js

var a = 2
 , b = '4'
 , c = b + a
 , d = b - a
 , e = c + d
 ;

console.log(typeof a, a);
console.log(typeof b, b);
console.log(typeof c, c);
console.log(typeof d, d);
console.log(typeof e, e);