localize_it 1.1.0

Simple and fast library for localization
Documentation

localize_it – Simple and fast localization library

Tests Crates.io Documentation License

A tiny, zero-allocation localization system for Rust designed with #![no_std] support.

This crate provides a macro-based API for defining compile-time locales and localized string expressions without using dynamic memory, hash maps, or runtime lookups. All localized strings are stored in fixed-size arrays, and the active locale is stored in an atomic variable, making access extremely fast and thread-safe.

Quick Example

use localize_it::{init_locale, expression, localize};

init_locale!(EN, RU);

expression!(HELLO => {
    EN: "Hello",
    RU: "Привет",
});

fn main() {
    println!("{}", localize!(HELLO));
}

Features

  • O(1) localization lookup
  • Zero allocations
  • no_std compatible
  • Thread-safe global locale (AtomicUsize)
  • Macro-based API
  • No external dependencies

Design Constraints

  • Locales are defined at compile time
  • Expressions must be &'static str

Example With Recommended Project Structure

The recommended usage pattern is to create a dedicated locale module that contains locale initialization and grouped expression modules. For example:

src/
├─ main.rs
└─ locale/
   ├─ mod.rs     # Locale initialization
   ├─ error.rs   # Expression module for error messages
   └─ ui.rs      # Expression module for UI elements

// mod.rs

pub mod error;
pub mod ui;

use localize_it::init_locale;

// Initialize locale with two languages
init_locale!(EN, RU);

// error.rs

use crate::locale::Expression;

// Expressions can be created manually without the macro
pub const COOKIE_BUTTON: Expression = [
    "Sorry, the button doesn't work",
    "Извините, кнопка не работает",
];

// ui.rs

use crate::locale::Locale;
use localize_it::expression;

// Recommended way to create expressions using the macro
expression!(COOKIE_BUTTON => {
    EN: "Click to get a cookie",
    RU: "Нажмите, чтобы получить печенье",
});

// main.rs (or wherever you want to use the localized strings)

use crate::locale::{error, get_locale, set_locale, ui, Locale};
use localize_it::localize;

fn main() {
    let current_locale = get_locale(); // Get current locale
    println!("{:?}", current_locale);

    set_locale(Locale::RU); // Set locale

    // Get one expression
    let button_error = localize!(error::COOKIE_BUTTON);
    println!("{}", button_error);

    // Get another expression
    let button_label = localize!(ui::COOKIE_BUTTON);
    println!("{}", button_label);
}

Usage

Add the following to your Cargo.toml:

[dependencies]

localize_it = "1.1.0"

How It Works

  • Locales are defined as an enum with #[repr(usize)]
  • Each localized string is compiled into a fixed-size &'static str array
  • The active locale is stored as an atomic integer
  • Localization resolves to a simple array index operation

License

This project is licensed under either of

at your option.