goodbedford

var someArray = [1, 2, 3, [11, 22, 33]];

console.log("array object:", someArray);
console.log("array to string:", someArray.toString());

goodbedford

var a; // is undefined 
var b = "name"; // is defined 
console.log("A:" + a); // prints undefined 
console.log("B:" + b); // prints "name" 
console.log("C" + c); // ReferenceError not defined

goodbedford

// this is a single line comment 
var a = 5; // single line comment after legit code 
var a = 5; // single line comment, commenting out the code 
/* this is a multi-line comment 
   this is a multi-line comment 
*/  

goodbedford

var str = "I am a string variable that is declared and defined"; 
console.log("I am a string"); // I am a string to console  
console.log(str); // I am a string variable that is declared and defined

goodbedford

// order of precedence are the rules for the order in which value gets evaluated

console.log("1 * 2 + 3 * 2 =", 1 * 2 + 3 * 2);

console.log("1 * 2 + 3 * 2 * 5 =", 1 * 2 + 3 * 2 *5);

console.log("5 +1 * 2 + 3 * 2 * 5 =", 5 +1 * 2 + 3 * 2 * 5 );

goodbedford

// relational operators compare greater than, less than, or equal to

var a = 10;
var b = 5;

// a is greater than b
console.log("a is greater than b:", a > b);

// b is not greater than a
console.log("b is greater than a:", b > a);

goodbedford

// arithmetic operators are your standard math operators
// we have addition + , subtraction - , multiplication * , division /, modulo/remainder %,

var a = 10;
var b = 5;
var c = 22;


// addition +
console.log("a + b =", a + b);

goodbedford

// strict equality comparison operator is the triple equals ( === )
// this checks for exact equality in value and type
var a = 4;
var b = 4;
var c = "4";


// both a and b are numbers
console.log("a === b is:", a === b);

goodbedford

// = the equal sign is the assignment operator;
var a = 10; // number ten is assigned to variable a;
var b = 20;
var c = 12;
a = c;  // a is 12
console.log("a: " + a);
a = c = b;  // a is 20, c is 20, b is 20
console.log("a: " + a);

goodbedford

// Promise.all is good for executing many promises at once
Promise.all([
  promise1,
  promise2
]);

// Promise.resolve is good for wrapping synchronous code
Promise.resolve().then(function () {
  if (somethingIsNotRight()) {
    throw new Error("I will be rejected asynchronously!");