ysm-dev

foo() // Uncaught TypeError: foo는 함수가 아닙니다
var foo = function() {
  console.log('FOOOOO')
}

ysm-dev

const transformNamesToUppercase = function(names) {
  const results = [];
  for (let i = 0; i < names.length; i++) {
    results.push(names[i].toUpperCase());
  }
  return results;
};
transformNamesToUppercase(names); // ['IRISH', 'DAISY', 'ANNA']

ysm-dev

function curry(fn) {
  if (fn.length === 0) {
    return fn
  }

  function _curried(depth, args) {
    return function(newArgument) {
      if (depth - 1 === 0) {
        return fn(...args, newArgument)
      }

ysm-dev

console.log('This is line one.\n' +
	'This is line two.');
// This is line one.
// This is line two.

ysm-dev

// 변수 교환
let a = 1
let b = 3

;[a, b] = [b, a]
console.log(a) // 3
console.log(b) // 1

ysm-dev

function foo() {
  // 함수 내에서 모든 변수에 접근할 수 있습니다.
  var bar = 'bar'
  let baz = 'baz'
  const qux = 'qux'

  console.log(bar) // "bar"
  console.log(baz) // "baz"
  console.log(qux) // "qux"
}

ysm-dev

var person = { name: 'Tyler', age: 28 };
console.log('Hi, my name is ' + person.name + ' and I am ' + person.age + ' years old!');
// 'Hi, my name is Tyler and I am 28 years old!'

ysm-dev

console.log(foo) // undefined

var foo = 'foo'

console.log(baz); // ReferenceError: can't access lexical declaration 'baz' before initialization

let baz = 'baz';

console.log(bar); // ReferenceError: can't access lexical declaration 'bar' before initialization

ysm-dev

// ES5 함수 생성자
function Person(name) {
  this.name = name
}

// ES6 클래스
class Person {
  constructor(name) {
    this.name = name
  }

ysm-dev

var foo = 'foo'
var foo = 'bar'
console.log(foo) // "bar"

let baz = 'baz'
let baz = 'qux'; // Uncaught SyntaxError: Identifier 'baz' has already been declared