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Depth in Event Loop

For those JavaScript programmers, event loop is an important concept, inevitably.

Literally, event loop is what JavaScritp uses to implement non-blocking execution. Understanding how the event loops works internally would benefit you a lot when programming in JavaScript.

There are two major environments JavaScript runs in: browser and Node.js.

Browser

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debugger;

var a; 

if (true) {
  a = {a: 2};
  function a() {}
  a.ot = '9'; 
  a = {a: 4};
  console.log('1', a);

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const NoopPromise = {
  then: () => NoopPromise,
  catch: () => NoopPromise,
};

Promise.resolve().then(() => {
  const number = Math.random();
  if (number > 0.5) {
    return number;
  }

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/**
The zero-width space character is encoded in Unicode as U+200B ZERO WIDTH SPACE (HTML ​)
*/
function insertSpaces(string){
  return Array.from(string).join('\u200b');
}

// see more at https://en.wikipedia.org/wiki/Zero-width_space
        

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process.stdin.resume();
process.stdin.setEncoding('ascii'); // 'utf-8' also supported 

let _input = "";

process.stdin.on('data', function (data) {
  _input += data;
});

process.stdin.on('end', function () {

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const fse = require('fs-extra');
const path = require('path');

const isNotDot = (filepath) => {
    const REG = /^\..+/i;
    return !REG.test(filepath);
};

/**
 * calculate the relative path from `start` to `end`

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let nowTop = 0;
const bodyEl = document.body;

export default mute => {
    if (mute) {
        nowTop = window.scrollY;

        bodyEl.style.position = 'fixed';
        bodyEl.style.top = -nowTop + 'px';
    } else {

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Reading

Catergroy

• Miscellany
• Angular
• User Interface
• JavaScript

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import React, { createContext, useReducer, useContext, Fragment } from 'react';
import './App.css';

const authReducer = (state, action) => {
  switch (action.type) {
    case 'increment':
      return {
        ...state,
        age: state.age + 1
      };