Getting Started

Installation

First, install the @aleksejdix/ally-bcp47 package using npm, yarn, or pnpm:

# npm
npm install @aleksejdix/ally-bcp47

# yarn
yarn add @aleksejdix/ally-bcp47

# pnpm
pnpm add @aleksejdix/ally-bcp47

Basic Usage

Here's a simple example of how to use the library:

import { validateLanguageTag, isValid } from "@aleksejdix/ally-bcp47";

// Quick validation
const isValidTag = isValid("en-US"); // true

// Detailed validation
const result = validateLanguageTag("en-US");
console.log(result.isValid); // true
console.log(result.isWellFormed); // true
console.log(result.tag); // { tag: 'en-US', language: 'en', region: 'us' }

// Invalid tag example
const invalidResult = validateLanguageTag("en-ZZ");
console.log(invalidResult.isValid); // false
console.log(invalidResult.errors);
// [{
//   type: 'unknown_subtag',
//   message: 'Unknown region subtag: ZZ',
//   subtag: 'ZZ',
//   subtagType: 'region'
// }]

When to Use This Library

The @aleksejdix/ally-bcp47 library is particularly useful in the following scenarios:

1. Internationalization (i18n): When building multilingual applications
2. Web Accessibility: Ensuring proper language identification for screen readers
3. Content Management Systems: Validating user-entered language preferences
4. Data Validation: Ensuring language codes in your database are valid
5. Compliance Requirements: Meeting ADA, Section 508, or EAA requirements

Features Overview

The library provides several key functions:

• validateLanguageTag(): Comprehensive validation with detailed results
• isValid(): Quick check if a tag is valid
• isWellFormed(): Check if a tag follows the correct syntax
• parseTag(): Parse a tag into its component parts
• canonicalizeTag(): Normalize a tag to its canonical form

Next Steps

Explore the following sections to learn more:

• Language Tags - More about BCP-47 tag structure
• Validation - Detailed validation options
• Canonicalization - How to normalize tags
• Accessibility Compliance - Meeting accessibility standards