ctl10n (compile time localization) provides you a simple way to embed messages
into binary file without embedding them into source. Internally, ctl10n generates
simple macro_rules! macro tr!() from provided TOML file with strings.
Put following to your build.rs:
rust
fn main() {
println!("cargo:rerun-if-changed:build.rs");
println!("cargo:rerun-if-chaged:strings.toml");
if let Err(err) = ctl10n::convert_default_strings_file() {
panic!("{}", err);
}
}
This will generate file $OUT_DIR/strings.rs from strings.toml.
TOML file with strings must be table where all values are strings. Example strings.toml:
toml
message = "Some message"
message-with-args = "Some message with {arg}"
You should include strings.rs somewhere (for example, in lib.rs) to use generated
macro. You can do this by calling macro ctl10n::include_strings!() or manually,
using include!().
After including macro it can be used like this:
```rust
ctl10n::include_strings!();
fn main() {
// tr!() with one argument will be translated to string literal
println!(tr!("message"));
println!(tr!("message-with-args"), arg = "foobar");
// tr!() with multiple arguments will be translated to formatted &String
println!("{}", tr!("message-with-args", arg = "foobaz"))
}
Output of this code (assuming `strings.toml` from above):
Some message
Some message with foobar
Some message with foobaz
```
Trying to use unknown key or wrong format arguments is compile-time error.