IT & Tech

https://meetup.toast.com/posts/130

https://developer.mozilla.org/ko/docs/Web/JavaScript/Reference/Global_Objects/Date

yarn start error방지

    "scripts": {
        "start": "PORT=8000 react-scripts start", //PORT=8000 삭제해야 yarn start error안남
        "build": "react-scripts build",
        "test": "react-scripts test --env=jsdom",
        "test:debug": "react-scripts test --env=jsdom --verbose false",
        "lint": "eslint src",
        "eject": "react-scripts eject"
    },

Redux사용을 위한 변경 (Window에서 개발하기 위해서 추가했던 것 같음)

before

import { createStore, applyMiddleware } from 'redux';
import thunkMiddleware from 'redux-thunk';
import cdp from '../reducers';
export default function configureStore (initialState) {
    const store = createStore(
        cdp,
        initialState,
        applyMiddleware(thunkMiddleware)
    );
    return store;
}

↓

after

import { createStore, applyMiddleware, compose(얘도추가함) } from 'redux';
import thunkMiddleware from 'redux-thunk';
import cdp from '../reducers';
export default function configureStore (initialState) {

    const composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;//이부분 추가

    const store = createStore(
        cdp,
        initialState,
        composeEnhancers(applyMiddleware(thunkMiddleware))//이부분 추가
    );
    return store;
}

* Promise: http://webframeworks.kr/tutorials/translate/es6-promise-api-1/

• async-await ()
  • await 키워드로 Promise 를 기다린다
  • 함수앞에 async 키워드를 붙여준다
  • 에러 처리는 try-catch 로 한다
  • async 함수의 반환값은 Promise 형태이다

https://velopert.com/2597

Map: Array를 다른 Array로 변환

매개변수는 순서대로 currentValue[, index[, array]]인듯

매개변수 이름을 중요하지 않고 순서만 중요한듯... 헷갈리는 개념!!! 알아두자!!!

참고) https://developer.mozilla.org/ko/docs/Web/JavaScript/Reference/Global_Objects/Array/map