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15.5.11 Rust ¶

RPMs

rust, rust-cargo

Ubuntu packages

rustc, cargo

File extension

rs

String syntax

"abc", r"abc", r#"abc"# etc.

gettext shorthand

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gettext/ngettext functions

gettext, ngettext

textdomain

textdomain function

bindtextdomain

bindtextdomain function

setlocale

setlocale function

Prerequisite

$ cargo add gettext-rs

use gettextrs::*;

Note: We recommend the ‘gettext-rs’ crate. We do not recommend the ‘gettext’ crate, because (as of 2025) it does not handle catalog fallback (e.g. from de_AT to de) nor the LANGUAGE environment variable.

Use or emulate GNU gettext

use

Extractor

xgettext

Formatting with positions

There are three common ways of doing string formatting in Rust:

• Using the built-ins format!, println!, etc. This facility supports only constant strings, known at compile-time. Thus it cannot be used with translated format strings. You would get an error such as “error: format argument must be a string literal”.
• Using the strfmt library. The facility cannot be recommended, because it does not support the case where some of the values are strings and some of the values are numbers (without an excessive amount of contortions).
• Using the formatx library. This is the one we recommend.

So, you have to convert the format!, println!, etc. invocations to use formatx. For example,

println!("Hello {}, you got {} coins.", name, left);

becomes

println!("{}", formatx!(gettext("Hello {}, you got {} coins."),
                        name, left)
               .unwrap());

For swapped positions, a translator may translate "Hello {}, you got {} coins." with "Hello, {1} coins are left for you, {0}."

Portability

fully portable

po-mode marking

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An example is available in the examples directory: hello-rust.