dmitry-tuzenkov

import { useCallback, useEffect } from 'react';

function useDebounceEffect(
  effect: () => void,
  delay: number | undefined,
  deps: any[]
) {
  const callback = useCallback(effect, deps);

  useEffect(() => {

dmitry-tuzenkov

type JobFunction<T> = () => Promise<T>;

async function promiseAll<T>(
jobs: JobFunction<T>[],
concurrency: number = Infinity,
): Promise<T[]> {
const results: T[] = new Array(jobs.length).fill(0);
const queue = new Array(concurrency).fill(Promise.resolve());
// const queue = jobs.splice(0, concurrency).map((fn: JobFunction<T>) =>
// fn().then((result: T) => {

dmitry-tuzenkov

interface User {
  id: number;
}

const storageCache = new Map<number, Promise<User>>();

function fetchUser(id: number): Promise<User> {
  console.log('id', id)
  return new Promise((res) => {
    setTimeout(() => res({ id }), 2000);

dmitry-tuzenkov

const versions = [
  "0.4",
  "0.11",
  "0.4.1",
  "0.4",
  "0.4.2",
  "2.0.1",
  "2",
  "0.0.1",
  "0.2.3",

dmitry-tuzenkov

node ./none-memo && node ./memo

none_memo: 10.005s
memo: 989.782ms

node ./none-memo && node ./memo
none_memo: 9.897s
memo: 974.547ms
node ./none-memo && node ./memo
none_memo: 9.953s

dmitry-tuzenkov

// Here is our log file; essentially a list of tuples.
// Each tuple has two items: `(request_path, user_id)`
const logFile = [
  ["/", "user_1"],
  ["/about", "user_1"],
  ["/", "user_3"],
  ["/features", "user_1"],
  ["/about", "user_2"],
  ["/purchase", "user_2"],
  ["/purchase", "user_1"],

dmitry-tuzenkov

const APLHA_MOD = 26;
const nt = (n = 0) => ((n % APLHA_MOD) + 10).toString(APLHA_MOD + 10);

const ct = (n = 0, acc = "") => {
  if (n - APLHA_MOD > 0) {
    return ct(n - APLHA_MOD, acc + nt(APLHA_MOD));
  }

  return acc + nt(n);
};

dmitry-tuzenkov

const _get = require('lodash.get')
const _isEmpty = require('lodash.isempty')
const _sumBy = require('lodash.sumby')
const _max = require('lodash.max')
const _flatten = require('lodash.flatten')
const _last = require('lodash.last')
const _size = require('lodash.size')
const _first = require('lodash.first')

const _map = (arr = [], fn) => Array.from(arr).map(fn)

dmitry-tuzenkov

const assert = require('assert')
const debug = require('debug')('app:aws-sqs')
const {
  SQSClient,
  DeleteMessageCommand,
  SendMessageCommand,
  ReceiveMessageCommand,
} = require('@aws-sdk/client-sqs')

const { pack } = require('./utils-data')

dmitry-tuzenkov

/* eslint-disable indent */

/**
 * Create a promise wrapper for function(err, arg1, ...argN)
 * @param {function} fn - Function that should be promisified
 * @returns {function} - Promisified function fn wrapper
 * @example <caption>Example usage of promisify.</caption>
 * const asynFn = require(...) // asynFn((err, a, b) => { ... })
 * const pMyFn = promisify(asynFn)
 * console.log('asynFn result', await pMyfn(1, 2))