fast-plural-rules

Fast Plural Rules

Evaluates locale-specific plural rules to identify the right plural form for a cardinal number, which represents an item count. Internationalization libraries can utilize it to choose the right localized string.

• Focused and complete - nothing but the rule evaluation is included, but still supporting almost 150 languages.
• Tiny and fast - 3 kB minified, 1 kB gzipped. Using plain hand-coded functions as plural rules to pick plural forms.
• Reliable and correct - written using the Translate Project documentation and the Mozilla documentation.

Table of Contents

• Synopsis
• Installation and Getting Started
• Usage Scenarios
• Design Concepts
• Supported Languages
• API Reference
• Library Integrations
• Contributing
• Release History
• License

Synopsis

const { getPluralFormForCardinalByLocale } = require('fast-plural-rules')

// Returns index of the plural form for the specified locale and cardinal.
getPluralFormForCardinalByLocale('en', 1) // Returns 0; "1 file"
getPluralFormForCardinalByLocale('en', 2) // Returns 1; "2 files"
getPluralFormForCardinalByLocale('en', 5) // Returns 1; "5 files"
getPluralFormForCardinalByLocale('cs', 1) // Returns 0; "1 soubor"
getPluralFormForCardinalByLocale('cs', 2) // Returns 1; "2 soubory"
getPluralFormForCardinalByLocale('cs', 5) // Returns 2; "5 souborů"

// English: 0 - singular
//          1 - plural
// Czech:   0 - singular
//          1 - plural for 2-4 items
//          2 - plural for 5+ items

Installation and Getting Started

This module can be installed in your project using NPM or Yarn. Make sure, that you use Node.js version 6 or newer.

$ npm i fast-plural-rules --save

$ yarn add fast-plural-rules

Functions are exposed as named exports, for example:

const { getPluralFormForCardinalByLocale } = require('fast-plural-rules')

You can read more about the module loading in other environments, like with ES6 or in web browsers. Usage scenarios demonstrate applications of this library in typical real-world situations. Design concepts explain the approach to the correct internationalization of messages with cardinals taken by this library. Translators will read about plural rules for supported languages to be able to write the right plural forms to language packs. Finally, the API reference lists all functions with a description of their functionality.

Library Integrations

• Extended Day.js - relativeTime plugin formats time durations to the past and to the future.

Contributing

In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using Grunt.

Release History

• 2018-10-28 v0.0.1 Initial release

License

Copyright (c) 2018 Ferdinand Prantl

Licensed under the MIT license.

Changelog

2018-10-28 v0.0.1

Initial release