bcp47

The bcp47 package does what it says on the tin - it parses BCP 47 language tags into their component parts. The API is straightforward: call `bcp47.parse()` and get back an object with language, script, region, and variants. However, the developer experience leaves much to be desired in 2024.

The biggest pain point is the complete absence of TypeScript definitions. There's no @types package either, so you're flying blind without autocompletion or type safety. The returned object structure is undocumented in the README - you'll need to console.log to discover the shape. Error handling is minimal; invalid tags return partial results rather than throwing or returning validation status, making it unclear if parsing succeeded.

The package hasn't been updated since 2015, which shows. No ESM support, minimal documentation (literally just a single example in the README), and no guidance on edge cases. For simple parsing needs it technically works, but you'll spend time reverse-engineering behavior that should be documented.

The bcp47 package does one thing: parse BCP 47 language tags into their constituent parts. It works correctly for basic parsing, but the developer experience is severely lacking. There are no TypeScript definitions whatsoever, forcing you to write your own interface definitions or work without type safety. The API is simple (just parse the tag and get an object back), but there's no validation feedback beyond returning null for invalid tags.

The package hasn't been updated since 2015, which shows in its dated approach. Documentation is extremely sparse—basically just a README with a single example. You'll need to reference the BCP 47 spec directly to understand what properties the parsed object contains. Error handling is non-existent; invalid tags silently return null with no information about what went wrong.

For modern projects, you're better off using alternatives like @stdlib/bcp47-parse or Intl.Locale (built into modern JavaScript). This package might work for legacy codebases where you just need basic parsing and can tolerate the lack of types, but it's hard to recommend for new development.

This is a straightforward synchronous parser that does exactly one thing: parse BCP 47 language tags into their component parts. The API is dead simple - you call parse() and get back an object with schema, language, extlang, script, region, variant, extension, and privateuse fields. It's fast, has zero dependencies, and the memory footprint is negligible since it's just regex-based parsing with no state.

The main operational concern is that this package hasn't been updated since 2015. While BCP 47 is stable, the lack of maintenance means no TypeScript definitions are bundled, error messages are sparse, and there's no logging hooks whatsoever. Error handling is minimal - invalid tags return an object with an error property, but you need to manually check for it. No async variants exist, though for this use case sync is probably fine.

For production use, you'll want to wrap this in your own error handling and validation layer. It works reliably for basic parsing needs, but consider more actively maintained alternatives like @phenomnomnominal/bcp-47 or Intl.Locale (built-in) for new projects.