Notes

What will the code below output to the console?

(function(){
var a = b = 3;
})();

console.log( (typeof b !== 'undefined'));

True

What will the code below output? Explain your answer.

console.log(0.1 + 0.2 == 0.3);

False

What will be the output of the following code

for (var i = 0; i < 5; i++) {
setTimeout(function() { console.log(i); }, i * 1000 );
}

5, 5, 5, 5, 5

What will be the output of the following code:

for (var i = 0; i < 5; i++) {
(function(x) {
setTimeout(function() { console.log(x); }, x * 1000 );
})(i);
}

0, 1, 2, 3, 4

What will be the output when the following code is executed?.

console.log(false === '0')

False

What is the output out of the following code? Explain your answer.
var a={},
b={key:'b'},
c={key:'c'};

a[b]=123;
a[c]=456;

console.log(a[b]);

456


Consider the code snippet below. What will the console output?
(function(x) {
return (function(y) {
console.log(x);
})(2)
})(1);

1

What will the following code output to the console:

var hero = {
_name: 'John Doe',
getSecretIdentity: function (){
return this._name;
}
};

var stoleSecretIdentity = hero.getSecretIdentity;
console.log(stoleSecretIdentity());

undefined

hat is the output of the following code?

var length = 10;
function fn() {
console.log(this.length);
}

var obj = {
length: 5,
method: function(fn) {
fn();
arguments[0]();
}
};

obj.method(fn, 1);

2,10

Consider the following code. What will the output be?

(function () {
try {
throw new Error();
} catch (x) {
var x = 1, y = 2;
console.log(x);
}

})();

1

What will be the output of this code?

var x = 21;
var girl = function () {
console.log(x);
var x = 20;
};
girl ();

undefined

What do the following lines output?

console.log(3 > 2 > 1);

False

What would following code return?

console.log(typeof typeof 1);

string

What will the following code output?

var b = 1;
function outer(){
var b = 2
function inner(){
b++;
var b = 3;
console.log(b)
}
inner();
}
outer();

3

What will be the output of the code below?

function isInt(num) {
return num % 1 === 0;
}
console.log(isInt(12.2));

False

What will be the output of the code below?
var y = 1;
if (function f(){}) {
y += typeof f;
}
console.log(y);

1undefined

What will be the output of the following code?

var output = (function(x){
delete x;
return x;
})(0);

console.log(output);

1

What will be the output of the code below?
var x = { foo : 1};
var output = (function(){
delete x.foo;
return x.foo;
})();

console.log(output);

undefined

What will be the output of the code below?
var Employee = {
company: 'xyz'
}
var emp1 = Object.create(Employee);
delete emp1.company
console.log(emp1.company);

xyz

What will be the output of the following code:

for (let i = 0; i < 5; i++) {
setTimeout(function() { console.log(i); }, i * 1000 );
}

0, 1, 2, 3, 4