PHP's krsort in JavaScript

How to use

You you can install via yarn add locutus and require this function via const krsort = require('locutus/php/array/krsort').

It is important to use a bundler that supports tree-shaking so that you only ship the functions that you actually use to your browser, instead of all of Locutus, which is massive. Examples are: Parcel, webpack, or rollup.js. For server-side use this is typically less of a concern.

Examples

Please note that these examples are distilled from test cases that automatically verify our functions still work correctly. This could explain some quirky ones.

#	code	expected result
1	var $data = {d: 'lemon', a: 'orange', b: 'banana', c: 'apple'} krsort($data) var $result = $data	{d: 'lemon', c: 'apple', b: 'banana', a: 'orange'}
2	ini_set('locutus.sortByReference', true) var $data = {2: 'van', 3: 'Zonneveld', 1: 'Kevin'} krsort($data) var $result = $data	{3: 'Zonneveld', 2: 'van', 1: 'Kevin'}

PHP arrays and JavaScript

Please note that Locutus uses JavaScript objects as substitutes for PHP arrays, they are the closest we can get to this hashtable-like data structure without rolling our own. While many JavaScript implementations preserve the order of object properties, the ECMAScript Language Specification explicitly states that:

The mechanics and order of enumerating the properties is not specified.

So don't use this for anything serious if you rely on the order to be consistent accross platforms.

To influence how Locutus treats objects to arrays, you can check out the `locutus.objectsAsArrays` setting.

Notes

• The examples are correct, this is a new way This function deviates from PHP in returning a copy of the array instead of acting by reference and returning true; this was necessary because IE does not allow deleting and re-adding of properties without caching of property position; you can set the ini of “locutus.sortByReference” to true to get the PHP behavior, but use this only if you are in an environment such as Firefox extensions where for-in iteration order is fixed and true property deletion is supported. Note that we intend to implement the PHP behavior by default if IE ever does allow it; only gives shallow copy since is by reference in PHP anyways Since JS objects’ keys are always strings, and (the default) SORT_REGULAR flag distinguishes by key type, if the content is a numeric string, we treat the “original type” as numeric.

Here’s what our current JavaScript equivalent to PHP's krsort looks like.

module.exports = function krsort(inputArr, sortFlags) {
  //  discuss at: https://locutus.io/php/krsort/
  // original by: GeekFG (https://geekfg.blogspot.com)
  // improved by: Kevin van Zonneveld (https://kvz.io)
  // improved by: Brett Zamir (https://brett-zamir.me)
  // bugfixed by: pseudaria (https://github.com/pseudaria)
  //      note 1: The examples are correct, this is a new way
  //      note 1: This function deviates from PHP in returning a copy of the array instead
  //      note 1: of acting by reference and returning true; this was necessary because
  //      note 1: IE does not allow deleting and re-adding of properties without caching
  //      note 1: of property position; you can set the ini of "locutus.sortByReference" to true to
  //      note 1: get the PHP behavior, but use this only if you are in an environment
  //      note 1: such as Firefox extensions where for-in iteration order is fixed and true
  //      note 1: property deletion is supported. Note that we intend to implement the PHP
  //      note 1: behavior by default if IE ever does allow it; only gives shallow copy since
  //      note 1: is by reference in PHP anyways
  //      note 1: Since JS objects' keys are always strings, and (the
  //      note 1: default) SORT_REGULAR flag distinguishes by key type,
  //      note 1: if the content is a numeric string, we treat the
  //      note 1: "original type" as numeric.
  //   example 1: var $data = {d: 'lemon', a: 'orange', b: 'banana', c: 'apple'}
  //   example 1: krsort($data)
  //   example 1: var $result = $data
  //   returns 1: {d: 'lemon', c: 'apple', b: 'banana', a: 'orange'}
  //   example 2: ini_set('locutus.sortByReference', true)
  //   example 2: var $data = {2: 'van', 3: 'Zonneveld', 1: 'Kevin'}
  //   example 2: krsort($data)
  //   example 2: var $result = $data
  //   returns 2: {3: 'Zonneveld', 2: 'van', 1: 'Kevin'}

  const i18nlgd = require('../i18n/i18n_loc_get_default')
  const strnatcmp = require('../strings/strnatcmp')

  const tmpArr = {}
  const keys = []
  let sorter
  let i
  let k
  let sortByReference = false
  let populateArr = {}

  const $global = typeof window !== 'undefined' ? window : global
  $global.$locutus = $global.$locutus || {}
  const $locutus = $global.$locutus
  $locutus.php = $locutus.php || {}
  $locutus.php.locales = $locutus.php.locales || {}

  switch (sortFlags) {
    case 'SORT_STRING':
      // compare items as strings
      sorter = function (a, b) {
        return strnatcmp(b, a)
      }
      break
    case 'SORT_LOCALE_STRING':
      // compare items as strings, based on the current locale
      // (set with i18n_loc_set_default() as of PHP6)
      var loc = i18nlgd()
      sorter = $locutus.locales[loc].sorting
      break
    case 'SORT_NUMERIC':
      // compare items numerically
      sorter = function (a, b) {
        return b - a
      }
      break
    case 'SORT_REGULAR':
    default:
      // compare items normally (don't change types)
      sorter = function (b, a) {
        const aFloat = parseFloat(a)
        const bFloat = parseFloat(b)
        const aNumeric = aFloat + '' === a
        const bNumeric = bFloat + '' === b
        if (aNumeric && bNumeric) {
          return aFloat > bFloat ? 1 : aFloat < bFloat ? -1 : 0
        } else if (aNumeric && !bNumeric) {
          return 1
        } else if (!aNumeric && bNumeric) {
          return -1
        }
        return a > b ? 1 : a < b ? -1 : 0
      }
      break
  }

  // Make a list of key names
  for (k in inputArr) {
    if (inputArr.hasOwnProperty(k)) {
      keys.push(k)
    }
  }
  keys.sort(sorter)

  const iniVal =
    (typeof require !== 'undefined' ? require('../info/ini_get')('locutus.sortByReference') : undefined) || 'on'
  sortByReference = iniVal === 'on'
  populateArr = sortByReference ? inputArr : populateArr

  // Rebuild array with sorted key names
  for (i = 0; i < keys.length; i++) {
    k = keys[i]
    tmpArr[k] = inputArr[k]
    if (sortByReference) {
      delete inputArr[k]
    }
  }
  for (i in tmpArr) {
    if (tmpArr.hasOwnProperty(i)) {
      populateArr[i] = tmpArr[i]
    }
  }

  return sortByReference || populateArr
}

A community effort

Not unlike Wikipedia, Locutus is an ongoing community effort. Our philosophy follows The McDonald’s Theory. This means that we assimilate first iterations with imperfections, hoping for others to take issue with-and improve them. This unorthodox approach has worked very well to foster fun and fruitful collaboration, but please be reminded to use our creations at your own risk. THE SOFTWARE IS PROVIDED "AS IS" has never been more true than for Locutus.

Now go and: [ View on GitHub | Edit on GitHub | View Raw ]

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