[](https://travis-ci.org/rust-locale/locale_config)
[](https://ci.appveyor.com/project/jan-hudec/locale-config/branch/master)
[](https://crates.io/crates/locale_config)
[](https://docs.rs/locale_config/)
# `locale_config`
Remembers locale configuration per-thread and per-process and initializes the
values by inspecting the system for user preferences.
## Installation
You can depend on this library by adding `locale_config` to your Cargo dependencies:
```toml
[dependencies]
locale_config = "*"
```
Usually it is not recommended to depend on `*`, but in this case it is
important that incompatible version requirements don't cause multiple
versions to be pulled in the final binary, so I do recommend it here and
promise I will maintain good compatibility. Just please don't add traits to
the types defined here to avoid conflicts with potential future methods.
## Using
Usually you want to use this indirectly via a localization crate like
`locale`. However if you need to work with the identifier itself, or you need
to override it, use
```rust
Locale::current()
```
to find what you should be using at any given point in the application,
```rust
Locale::set_current()
```
to override it for current thread and
```rust
Locale::set_global_default()
```
to override it for new threads.
In case you need to access the initial value, you'll find it under
```rust
Locale::user_default()
```
The value may contain language tags specific for various localization
aspects, called categories, and fallbacks. The `Locale::tags_for` method will
take care of selecting relevant tags for you. For preferred language of
translations, use
```rust
Locale::current().tags_for("messages")
```
For formatting, use categories `"numeric"` for numbers, `"time"` for date and
time and `"monetary"` for money amounts. And use `"collate"` for collation.
Note that this crate does not itself provide any translation, formatting nor
collation functionality. Formatting and collation will be provided by
`locale` crate, translation has multiple available implementations.
See full documentation on [](https://docs.rs/locale_config/) or [github](https://rust-locale.github.io/locale_config/locale_config/).
## Supported systems
* **Unix:** Using the POSIX standard environment variables `LANG`, `LC_*` and
`LANGUAGES`. The variables are recognized on all systems and take
precedence on most of them.
* **Windows:** Vista and newer
- Uses API available from Vista and Server 2008 only.
- The `GetUserPreferredUILanguages` is only available for desktop, but
not store applications. Store applications should have equivalent
functionality, but I didn't try accessing it from Rust yet.
- Customization to individual locale elements done in “Regional and
Language options” (digits, calendar, decimal and thousand separator
etc.) are not detected (yet).
- Not well tested.
* **OS X:** Reads setting from `NSLocale`, can be overridden by setting the
Unix environment variables.
* **CGI:** The `HTTP_ACCEPT_LANGUAGE` environment variable is used if
detected. Hopefully it is specific enough to the CGI environment that it
can be used whenever detected.
## Changelog
### 0.3.0
* Support OS X `NSLocale`.
Thanks Sophie Tauchert (@999eagle).
### 0.2.3
* Try support getting locale in emscripten targets in browser. Unfortunately
the emscripten targets seem to have broken in cross meanwhile, so they are not
being tested.
* Update to winapi 0.3.
* Update ro regex 1.0.
### 0.2.2
* Update dependencies: regex 0.2.
### 0.2.1
* Interpret some overrides that can be set on Windows in Region and Language
dialog, namely: group, decimal and list separators, first day of week,
12/24-hour time, measurement system, (decimal) number system, to an extent
negative monetary value format (only whether to use parenthesized format
or not) and to an extent date format (if ISO-8601 variant is selected).
### 0.2.0
* Changed error handling to proper error type.
### 0.1.1
* Added basic Windows support.
### 0.1.0
* Initial version, with Unix and CGI support.