[][src]Crate icu

icu is the main meta-package of the ICU4X project.

It provides a comperhensive selection of Unicode Internationalization Components in their canonical configurations intended to enable software internationalization capabilities.

The package is provided for convenience and users are encouraged to fine-tune components with the features they need.

The package does not bring any unique functionality. Users can achieve the exact same by manually including the dependent components with pre-selected features.

Data Management

Most of Unicode functionality relies on data which has to be provided to the APIs.

ICU4X project uses a concept of DataProvider - a service used to handle data management.

There can be many different heuristics for handling data management and this meta-package does not supply any default DataProvider.

When using ICU4X users are expected to decide which provider they want to use and instrument it to point at the correct location where the data files are stored.

In the following examples an icu_testdata package is used which wraps an FsDataProvider with locally available subset of data.


use icu::locid::macros::langid;
use icu::datetime::{DateTimeFormat, date::MockDateTime, options::style};

let provider = icu_testdata::get_provider();

let lid = langid!("en");

let options = style::Bag {
    date: Some(style::Date::Long),
    time: Some(style::Time::Medium),

let dtf = DateTimeFormat::try_new(lid, &provider, &options)
    .expect("Failed to create DateTimeFormat instance.");

let date: MockDateTime = "2020-09-12T12:35:00".parse()
    .expect("Failed to parse date.");

let formatted_date = dtf.format(&date);
assert_eq!(formatted_date.to_string(), "September 12, 2020 at 12:35:00 PM");



Date and Time operations


Language and Locale operations


Plural Rules operations


Unicode Set operations