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/*
look-and-say-sequence by Jaeho Lee,
public domain

1 => [[1, 1]]
11 => [[1, 2]]
21  => [[2, 1], [1, 1]]
1211
111221
*/

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// Promise exception handling is actually handled by mulitple level - therfore you need to care about many things
new Promise((res, rej) => {
    setTimeout(_ => {
      // case 1) error outside of promise context
      res('booom 2');
      throw new Error('error 2'); // this won't get ignored like case 1 and have to be catched manually. Also this don't automatically goes to `onRejected` handler unlike case 1.
    }, 3000);
    // case 2)
    // res('booom 1');
    // throw new Error('error 1'); // This gets ignored because it is thrown after resolve function gets called.

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function rgb2hsl(r, g, b){
    r = r/255, g = g/255, b = b/255;
    var max = Math.max(r, g, b), min = Math.min(r, g, b);
    var h, s, v = max;

    var d = max - min;
    s = max == 0 ? 0 : d / max;

    if(max == min){
        h = 0; // achromatic

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// ES5 lte
try {
  var a = {
    c:1, b: (function b() { return this.c }).bind(a)
  };
} catch(e) { console.warn(e); }

// ES2015
try {
  let a = {

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let __DEBUG_HTML = '';

function fetchLoc(locID){
    return fetch(`https://www.instagram.com/explore/locations/${locID}/`)
        .then(res => res.text())
        .then(txt => {
            __DEBUG_HTML = txt;
            const doc = parseInstgramExplorePage(txt);
            const sharedData = extractSharedData(doc);
            const locData = extractLocationData(sharedData);

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// This function can be impure in JS context...
function sum(arr) {
  var z = 0;
  for (var i=0;i<arr.length;i++) {
    z += arr[i];
  }
  return z;
}

// sec 1: valueOf() impureness

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import ReactDOM from 'react';


// render without using JSX
export function jsRender(Component, data={}, targetElement, callback=null) {
    ReactDOM.render(<Component {...data} />, targetElement, callback)
}

// Render after specific element. 
export function wrappedRenderCreator(

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function pp(givenNth/*: int*/, curNth = 0/*: int*/, dir = 1 /* { 1 | -1 } */, result = 0/*: int*/) { 
    // console.log(arguments[1], arguments[2], arguments[3]);
    'use strict';
    if (givenNth === curNth) {
        return result;
    } else {
        return pp(givenNth, curNth + 1, isTurnAround(curNth + 1) * dir, result + dir);
    }
}

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// %
function mod(num, by) {
    var tmp_num = num;
    while (tmp_num - by >= 0) {
        tmp_num -= by
    } 
    return tmp_num;
}

function fizzbuzzMod (limit) {

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export function debounceUntilTimeout(fun, delay, context = null) {
    var timer;
    return function delayedFunctionWrapper(...args) {
        clearTimeout(timer);
        args.unshift(context);
        timer = setTimeout(fun.bind.apply(fun, args), delay);
    };
}