gunar

/*
  Gunar C. Gessner
  @gunar 2016
  
  INSTALL: https://script.google.com/macros/s/AKfycbym7IaTORzJ7LQPcxMx1LV1SQEC6RVGv5tzLOgYS8iQe8XAJxM/exec
  
  After installation, the script will, every 10 minutes, search for all files that have duplicates (shift+z) and remove them from the root directory ("My Drive").

  This Google Apps Script webapp aims to solve the problem that when transferring ownership of folders &
  files to another account, duplicate files shown in "My Drive".

gunar

'use strict'

const { HDPublicKey, PublicKey, Address, Networks } = require('bitcore-lib')
const xpubkey = 'xpub...'
const hdPublicKey = HDPublicKey(xpubkey);

// We'll generate the first 20 addresses (default number of addresses that Electrum shows you)
for (let i = 0; i < 20; i++) {
  
  const orderPublicKey = hdPublicKey.deriveChild(`m/0/${i}`)

gunar

'use strict'

const toUpper = async string => {
  if (string === 'invalid') return [Error('Invalid input')]
  return [null, string.toUpperCase()]
}
const errorHandler = () => { console.log('There has been an error. I\'ll handle it.') }
const print = console.log

const foo = async input => {

gunar

'use strict'

// ref https://en.wikipedia.org/wiki/Cycle_sort
const cycleSort = array => {
  // last item will already be in place
  for (let cycleStart = 0; cycleStart < array.length-1; cycleStart++) {
    let item = array[cycleStart]

    // find where to put the item
    let pos = cycleStart

gunar

/**
 * Currying Functions with Named Parameters.
 * @gunar, @drboolean, @dtipson 2016
 * 
 * Why does it return a thunk, though?
 *   Because in JS named arguments are opaque. There is no way of getting a function's named arguments list.
 *   e.g.
 *     const foo = function ({ a, b }) { }
 *     console.log(foo.arguments) // Throws. Ideally would return ['a', 'b'].
 * 

gunar

import React, { useState, createRef } from "react";

const Form = () => {
  const emailRef = createRef<HTMLInputElement>()
  return (
    <div>
      Email:
      <input type="text" ref={emailRef}/>
      <button
        onClick={() => {

gunar

import React, { useState } from 'react'

const Form = () => {
  const [key, setKey] = useState(0)
  return (
    <div key={key}>
      <input type='text' />
      <button onClick={/* ... */}>Submit</button>
      <button onClick={() => { setKey(key + 1) }}>Reset</button>
    </div>

gunar

// Property-based test
describe('properties', () => {
  it('is a bijection', () => {
    fc.assert(fc.property(
      fc.integer(1, Number.MAX_SAFE_INTEGER),
      seed => decode(encode(seed)) === seed
    ))
  });
})

gunar

// Proof: https://www.typescriptlang.org/play/#src=type%20Woman%20%3D%20%7B%0D%0A%20%20id%3A%20Number%0D%0A%20%20husband%3F%3A%20string%0D%0A%7D%0D%0A%0D%0Atype%20With%3CT%2C%20K%20extends%20keyof%20T%3E%20%3D%20(Required%3CPick%3CT%2C%20K%3E%3E%20%26%20Exclude%3CT%2C%20K%3E)%0D%0Atype%20Without%3CT%2C%20K%20extends%20keyof%20T%3E%20%3D%20Pick%3CT%2C%20Exclude%3Ckeyof%20T%2C%20K%3E%3E%0D%0A%0D%0Aconst%20processMrs%20%3D%20(mrs%3A%20With%3CWoman%2C%20'husband'%3E)%20%3D%3E%20%7B%0D%0A%20%20%20%20const%20%7B%20husband%20%7D%20%3D%20mrs%0D%0A%20%20%20%20console.log(%60I%20now%20for%20a%20fact%20%24%7Bmrs%7D%20is%20married.%60)%0D%0A%7D%0D%0AprocessMrs(%7B%20id%3A%201%2C%20husband%3A%20'John'%20%7D)%20%20%20%20%2F%2F%20passes%0D%0AprocessMrs(%7B%20id%3A%202%2C%20husband%3A%20undefined%20%7D)%20%2F%2F%20fails%20(with%20strictNullChecks%3A%20true)%0D%0AprocessMrs(%7B%20id%3A%203%20%7D)%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%2F%2F%20fails%20(with%20strictNullChecks%3A%20true)%0D%0A%0D%0Aconst

gunar

// Property-based Testing example (pseudo-code).
test([Number],  anArrayOfNumbers => {
//   ↑↑↑↑↑↑↑↑↑↑   ↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑
// The schema.  The generated test-data.
  assert.deepEqual(
    mySort([anArrayOfNumbers]),
    Array.prototype.sort.call(anArrayOfNumbers)
  )
})