Utility FunctionsLocales
isSameLanguage
API Reference for the isSameLanguage function
Overview
The isSameLanguage function checks if multiple BCP-47 locale codes represent the same base language, ignoring regional differences.
Reference
Parameters
Prop
Type
Returns
boolean - true if all locale codes represent the same base language
Examples
import { isSameLanguage } from 'generaltranslation';
// Same language, different regions
console.log(isSameLanguage('en-US', 'en-GB')); // true
console.log(isSameLanguage('es-ES', 'es-MX')); // true
console.log(isSameLanguage('zh-CN', 'zh-TW')); // true
// Different languages
console.log(isSameLanguage('en-US', 'es-ES')); // false
console.log(isSameLanguage('fr-FR', 'de-DE')); // falseNotes
- Compares only base language codes (before first hyphen)
- Ignores regional, script, and variant differences
- Essential for language-based content organization
- Works with variable number of parameters
Next Steps
- Use GT class method isSameLanguage
- Compare dialects with isSameDialect
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