W3stside

interface SingleItemCache<R, A> {
  cachedArg?: R[]
  cachedValue?: A
}

export function cbCacheWrapper<R, A>(cb: Function): (...args: R[]) => A {
  // create cache in closure
  let singleItemCache: SingleItemCache<R, A> = {}

  // close over a cb

W3stside

// 1. Log blooms: https://web3js.readthedocs.io/en/v1.2.4/web3-utils.html?highlight=bloom#bloom-filters

// Specific topic you're looking for, typically topics are:

// 		Contract Event params must not be anonymous

// 		topics array: 
// 		1. topics[0] = keccak256 hashed entire signature of specific Event e.g Deposit(uint amt, address user)
//		2. topics[1] = keccak256 hashed 1st param i.e uint amt
//		3. topics[2] = keccak256 hashed 2nd param i.e address user

W3stside

// Add file-loader

// in Webpack.dev and .prod

// in module.rules[]
{
  test: /\.(pdf)$/i,
  use: {
    loader: 'file-loader',
    options: {

W3stside

// this gist is to show how, when using BigNumber JS
// one can display numbers in the FE using a set precision
// but without the issue of (assuming always precision 4)
// Numbers such as e.g 1 being shown as 1.000 or
// 1.00001 being show as 1.000

// this gist uses some typescript, just remove the typings in
// the function params if you're having problems

// using web3 v0.20

W3stside

/**
* EtherScan Validate Contract API
* URL: https://api.etherscan.io/api?module=contract&action=getabi&address=ContractAddressHere&apikey=YourApiKeyToken
* Checks contract address against database of approved Contracts
*/

const apiKey = 'yourEtherScanAPIKeyHere'

const checkContract = (addr, ak) =>
    fetch(`https://api.etherscan.io/api?module=contract&action=getabi&address=${addr}&apikey=${ak}`)

W3stside

// thanks Dmitry ^.^
let dynamicIdx = 15

const indexes = Array.from({ length: dynamicIdx }, (v, i) => dynamicIdx - i)

// spits out:
// [15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1]

W3stside

var json = {
    heading: 'Welcome to the app!',
    modal: {
      message: {
        alternate: 'Do you want to continue?',
        default: 'Are you sure?'
      },
      no: 'Cancel',
      yes: 'Continue',
    },

W3stside

/** Use NumGen to create a randomly sorted and filled Array to pass to quickSorter to test
* Can call quickSorter with numGen(<Number>) directly 
* e.g quickSorter(numGen(500)); 
*/

/** numGen
* @param {number} - length
* @param {limit} -  limit
* @returns {array}
*/

W3stside

/** Use arrGen to create a randomly sorted and filled Array to pass to quickSorter to test
* Can call quickSorter with numGen(<Number>) directly 
* e.g quickSorter(numGen(500)); 
*/

/** arrGen
* @param {number} - length
* @returns {array}
*/
const arrGen = (length, limit) => {