Fluent Locale is a library for language tags manipulations and negotiation.
This is a Rust implementation of fluent-locale library which is a part of Project Fluent.
The library allows for parsing language tags into Locale objects, operating on them
and serializing the result back to language tag strings.
On top of that, it allows for simple operations like comparing Locale objects and
negotiating between lists of language tags.
toml
[dependencies]
fluent_locale = "0.1.0"
```rust extern crate fluent_locale;
use fluentlocale::Locale; use fluentlocale::negotiate_languages;
let loc = Locale::from("fr-CA"); println!("Language: {}", loc.getlanguage()); println!("Script: {}", loc.getscript()); println!("Region: {}", loc.getregion()); println!("Variants: {}", loc.getvariants()); println!("Extensions: {}", loc.get_extensions());
let loc2 = Locale::from("fr-FR");
// The second and third parameters are allow for range matching if loc.matches(loc2, false, false) { println!("Locales are matching!"); }
let supported = negotiatelanguages( vec!["de-DE", "fr-FR", "en-US"], vec!["de-DE", "de-AT", "fr-CA", "fr", "en-GB", "en", "en-US", "it"], "en-US", fluentlocale::NegotiationStrategy::Filtering ); ```
The implementation is in early stage, but is complete according to fluent-locale corpus of tests, which means that it parses, serializes and negotiates as expected.
The remaining work is on the path to 1.0 is to gain in-field experience of using it, add more tests and ensure that bad input is correctly handled.
The API is based on BCP47 definition of Language Tags and is aiming to parse and serialize all language tags according to that definition.
Parsed language tags are stored as Locale objects compatible with
ECMA402's Intl.Locale and allow for operations on language tag subtags and
unicode extension keys as defined by RFC6067 and Unicode UTS35
Language negotiation algorithms are custom Project Fluent solutions, based on RFC4647.
The limitations of the current API is that it does allow for operations
only on language subtags other than basic (language, script, region, variants) and unicode
extension keys. Other subtags will be parsed and serialized, but there is no
API access to them when operating on the Locale object.
The language negotiation strategies aim to replicate the best-effort matches with the most limited amount of data. The algorithm returns reasonable results without any database, but the results can be improved with either limited or full [CLDR likely-subtags] database.
The result is a balance chosen for Project Fluent and may differ from other implementations of language negotiation algorithms which may chose different tradeoffs.
cargo build
cargo test
cargo bench