natural-compare-lite

What is natural-compare-lite?

The natural-compare-lite npm package is designed for comparing strings in a way that humans might naturally order them. This is particularly useful when sorting lists of strings that include numbers, as it ensures that numerical parts are compared numerically rather than lexicographically. For example, 'item2' will come before 'item10', which is not the case with standard string comparison.

What are natural-compare-lite's main functionalities?

Natural String Comparison

This feature allows for the natural comparison of strings, especially useful for sorting arrays where elements contain numbers. The provided code demonstrates sorting an array of strings in a natural order.

"use strict";\nconst naturalCompare = require('natural-compare-lite');\nconsole.log(['item10', 'item2'].sort(naturalCompare)); // ['item2', 'item10']

Other packages similar to natural-compare-lite

string-natural-compare

This package offers functionality similar to natural-compare-lite, providing natural string comparison capabilities. It differs in implementation details and possibly in performance characteristics, but serves a similar purpose of comparing strings in a human-friendly way.

alphanum-sort

Alphanum-sort is another package that provides natural string sorting capabilities. It allows for additional customization options such as case sensitivity and whether to treat whitespace and punctuation as part of the sorting criteria. This makes it a versatile alternative to natural-compare-lite, depending on the specific needs of a project.

README

@version    1.4.0
@date       2015-10-26
@stability  3 - Stable

Natural Compare –

Compare strings containing a mix of letters and numbers in the way a human being would in sort order. This is described as a "natural ordering".

Standard sorting:   Natural order sorting:
    img1.png            img1.png
    img10.png           img2.png
    img12.png           img10.png
    img2.png            img12.png

String.naturalCompare returns a number indicating whether a reference string comes before or after or is the same as the given string in sort order. Use it with builtin sort() function.

Installation

• In browser

<script src=min.natural-compare.js></script>

• In node.js: npm install natural-compare-lite

require("natural-compare-lite")

Usage

// Simple case sensitive example
var a = ["z1.doc", "z10.doc", "z17.doc", "z2.doc", "z23.doc", "z3.doc"];
a.sort(String.naturalCompare);
// ["z1.doc", "z2.doc", "z3.doc", "z10.doc", "z17.doc", "z23.doc"]

// Use wrapper function for case insensitivity
a.sort(function(a, b){
  return String.naturalCompare(a.toLowerCase(), b.toLowerCase());
})

// In most cases we want to sort an array of objects
var a = [ {"street":"350 5th Ave", "room":"A-1021"}
        , {"street":"350 5th Ave", "room":"A-21046-b"} ];

// sort by street, then by room
a.sort(function(a, b){
  return String.naturalCompare(a.street, b.street) || String.naturalCompare(a.room, b.room);
})

// When text transformation is needed (eg toLowerCase()),
// it is best for performance to keep
// transformed key in that object.
// There are no need to do text transformation
// on each comparision when sorting.
var a = [ {"make":"Audi", "model":"A6"}
        , {"make":"Kia",  "model":"Rio"} ];

// sort by make, then by model
a.map(function(car){
  car.sort_key = (car.make + " " + car.model).toLowerCase();
})
a.sort(function(a, b){
  return String.naturalCompare(a.sort_key, b.sort_key);
})

• Works well with dates in ISO format eg "Rev 2012-07-26.doc".

Custom alphabet

It is possible to configure a custom alphabet to achieve a desired order.

// Estonian alphabet
String.alphabet = "ABDEFGHIJKLMNOPRSŠZŽTUVÕÄÖÜXYabdefghijklmnoprsšzžtuvõäöüxy"
["t", "z", "x", "õ"].sort(String.naturalCompare)
// ["z", "t", "õ", "x"]

// Russian alphabet
String.alphabet = "АБВГДЕЁЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯабвгдеёжзийклмнопрстуфхцчшщъыьэюя"
["Ё", "А", "Б"].sort(String.naturalCompare)
// ["А", "Б", "Ё"]

External links

• GitHub repo
• npm package
• jsperf test

Licence

Copyright (c) 2012-2015 Lauri Rooden <[e-mail]>
The MIT License