10 releases
0.1.10 | Aug 11, 2024 |
---|---|
0.1.9 | Jun 12, 2023 |
0.1.8 | May 16, 2023 |
0.1.6 | Feb 14, 2021 |
0.1.0 | Nov 25, 2018 |
#54 in Internationalization (i18n)
77KB
1.5K
SLoC
Localisation of rust applications
This repository is an attempt to make it possible to localize rust application. There are two crates
-
tr
is a runtime library wrapping gettext (currently), in order to provide a convenient way to localize an application. -
xtr
is a binary similar to GNU'sxgettext
which extract string from a rust crate. It can extract strings of crate using thetr
macro from this sibling crate, or using other gettext based localisation crates such asgettext-rs
,gettext
,rocket_i18n
How to translate a rust application
-
Annotate the strings in your source code with the write macro/functions. You can use
- The the
tr!
macro from thistr
crate (still work in progress), or - The gettext function from the
gettext
or thegettext-rs
crate
- The the
-
Run the
xtr
program over your crate to extract the string in a .pot file -
Use the GNU gettext tools to merge, translate, and generate the .mo files
About tr!
- The name comes from Qt's
tr()
function. It is a short name since it will be placed on most string literal. - The macro can do rust-style formatting. This makes it possible to re-order the arguments in the translations.
Hello {}
orHello {0}
or HelloHello {name}
works.- Currently, the default backend uses the
gettext-rs
crate, but this could be changed togettext
in the future. - Plurals are handled by gettext, which support the different plurals forms of several languages.
Future plans
- Validity of the formatting in the original or translation is not done yet, but could be done in the future
- More advanced formatting that would allow for gender or case can be done as an extension to the formatting rules. Since the macro takes the arguments directly, it will be possible to extend the formatting engine with a scripting system or something like ICU MessageFormat.
- Formatting date/number in a localized fashion.
Example
#[macro_use]
extern crate tr;
fn main() {
// use the tr_init macro to tell gettext where to look for translations
tr_init!("/usr/share/locale/");
let folder = if let Some(folder) = std::env::args().nth(1) {
folder
} else {
println!("{}", tr!("Please give folder name"));
return;
};
match std::fs::read_dir(&folder) {
Err(e) => {
println!("{}", tr!("Could not read directory '{}'\nError: {}",
folder, e));
}
Ok(r) => {
// Singlular/plural formating
println!("{}", tr!(
"The directory {} has one file" | "The directory {} has {n} files" % r.count(),
folder
));
}
}
}
About xtr
xtr
is a tool that extract translated strings from the source code of a rust crate.
The tool is supposed to be compatible with any gettext based functions. But support for the
special syntax of the tr! macro has been added.
Usage
xtr src/main.rs -o example.pot
This will extract the strings from all the modules of the crate, and create a file example.pot
.
You can now use the gettext tools to translate this file.
Differences with xgettext
xtr
is basically to be used in place of xgettext
for Rust code.
xgettext
does not currently support the rust language. We can get decent result
using the C language, but:
xgettext
will not work properly if the code contains comments or string escaping that is not compatible with Rust's rules. (Rules for comments, or string escaping are different in Rust and in C. Think about raw literal, embedded comments, lifetime, ...)xtr
uses the lexer from theproc_macro2
crate so it parse rust code.xgettext
cannot be told to extract string out of a macro, whilextr
will ignore the!
token. Sogettext(...)
orgettext!(...)
will work.xgettext
cannot handle the rust rules within the string literal.xtr
will have no problem with rust's raw literal or rust's escape sequence.xtr
can also parse themod
keyword, and easily parse all the files in a crate.- Finally,
xtr
can also parse the more advanced syntax within thetr!
macro.
Licence
-
The
tr
crate is licensed under the MIT license. -
The
xtr
program is a binary used only for development and is in the GNU Affero General Public License (AGPL).
Contribution
Contributions are welcome. Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this crate by you, should be licensed under the MIT license.
Request for feedback
Please fill your suggestions as issues. Or help by commenting on https://github.com/woboq/tr/issues/1
Dependencies
~15–22MB
~122K SLoC