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/**
  Code for enumerating valid JSON strings.
  Bounds checking is the responsibility of the caller.
  The case N = 0 is intentionally not handled.

  This code attempts to be somewhat readable without significantly impacting performance.

  https://qntm.org/jsoncount
*/

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TypeScript: key-optional vs. value-optional

Normal object type with a required property

type Apple = { numPips: number }

const apple1: Apple = {}                     // ❌ type error
const apple2: Apple = { numPips: undefined } // ❌ type error
const apple3: Apple = { numPips: 3 } // ✅ valid

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import timersPromises from 'node:timers/promises'

const FEB = 1
const MAR = 2

// `setTimeout` disallows numbers which don't fit into a signed 32-bit integer.
// In other words
const MAX_DELAY = 2 ** 31 - 1

const add18Years = date => {

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const SIGN_BITS = 1n
const EXPONENT_BITS = 11n
const MANTISSA_BITS = 52n
const BIAS = 1023n

export const stringify = value => {
  if (typeof value !== 'number') {
    throw Error('Not a number')
  }

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class Item {
  constructor (name, sellIn, quality) {
    this.name = name
    this.sellIn = sellIn
    this.quality = quality
  }
}

class Shop {
  constructor (items = []) {

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// Exports a function which determines whether a JavaScript value is a power of
// two or not. Unlike the npm package `is-power-of-two`, this actually returns
// the correct answer in all cases.

const countSetBits = i => {
  // Based on <https://stackoverflow.com/a/109025/792705> but with some of the
  // performance optimisations reverted for the sake of improved legibility.
  i = (i & 0b01010101010101010101010101010101) + ((i & 0b10101010101010101010101010101010) >>> 1)
  i = (i & 0b00110011001100110011001100110011) + ((i & 0b11001100110011001100110011001100) >>> 2)
  i = (i & 0b00001111000011110000111100001111) + ((i & 0b11110000111100001111000011110000) >>> 4)

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const { UNICODE, seq } = require('green-parse')

const trend = UNICODE.plus().map(chars => chars.join(''))

// match e.g. "trend1, trend2, trend3" and return ["trend1", "trend2", "trend3"]
const trends = trend.plus(', ')

// match e.g. "trend1, trend2 and trend3" and return ["trend1", "trend2", "trend3"]
const trendsAndTrend = seq([trends, ' and ', trend])
  .map(([trends, and, trend]) => [...trends, trend])

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// AppScan may flag up a call like this as "Insecure Use of Document.Write"
// because it isn't intelligent enough to know that this a call to a totally
// unrelated method also named `write`
const diffBuffer = PNG.sync.write(diffPng)

// Replace with:
// eslint-disable-next-line no-useless-call
const diffBuffer = PNG.sync.write.call(PNG.sync, diffPng)

///////////////////////////////

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const nextafter = require('nextafter')

for (let i = -Infinity; i !== Infinity; i = nextafter(i, Infinity)) {
	console.log(i)
}

// Whoops, forgot a few the first time I ran this
console.log(Infinity)
console.log(NaN)

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// <https://twitter.com/Revolvolutionry/status/1165616879009816576>
// <https://oeis.org/A036746>

const { arabicToRoman, romanToArabic } = require('big-roman')

// The entry at index `i` in this array is the smallest Roman numeral
// of length `i`
const results = ['']
const stopAt = 281
let powerOfTen = 0