lux/docs/tutorials

Tutorials

Learn Lux by building real projects.

Standard Programs

These tutorials cover common programming tasks:

Tutorial	What You'll Build	Concepts
Calculator	REPL calculator	Parsing, evaluation, REPL loop
Todo App	CLI task manager	File I/O, data structures
HTTP Client	API consumer	HTTP effects, JSON parsing
Word Counter	Text analyzer	File reading, string ops

Effect Showcases

These tutorials demonstrate Lux's unique effect system:

Tutorial	What You'll Learn	Key Concept
Dependency Injection	Testing with mock handlers	Handler swapping
State Machines	Modeling state transitions	Custom effects
Effects Cookbook	Common effect patterns	Handler patterns

Quick Start: Your First Project

1. Create Project Directory

mkdir my-first-lux
cd my-first-lux

2. Create Main File

// main.lux

fn main(): Unit with {Console} = {
    Console.print("Welcome to my Lux project!")
    Console.print("Enter your name:")
    let name = Console.readLine()
    Console.print("Hello, " + name + "!")
}

let output = run main() with {}

3. Run It

lux main.lux

4. Add a Module

// lib/greetings.lux

pub fn hello(name: String): String =
    "Hello, " + name + "!"

pub fn goodbye(name: String): String =
    "Goodbye, " + name + "!"

// main.lux
import lib/greetings as greet

fn main(): Unit with {Console} = {
    Console.print("Enter your name:")
    let name = Console.readLine()
    Console.print(greet.hello(name))
    Console.print(greet.goodbye(name))
}

let output = run main() with {}

Project Ideas by Difficulty

Beginner

• Temperature converter - Convert between Celsius, Fahrenheit, Kelvin
• Number guessing game - Random number with hints
• Simple quiz - Multiple choice questions with scoring
• Unit converter - Length, weight, volume conversions

Intermediate

• Markdown previewer - Parse basic Markdown to HTML
• Contact book - CRUD with file persistence
• Simple grep - Search files for patterns
• CSV processor - Read, filter, transform CSV files

Advanced

• Test framework - Use effects for test isolation
• Config loader - Effect-based configuration with validation
• Mini interpreter - Build a small language
• Chat client - HTTP-based chat application

Effect Showcases

• Transaction system - Rollback on failure
• Capability security - Effects as capabilities
• Async simulation - Model async with effects
• Dependency graph - Track and inject dependencies

How to Use These Tutorials

1. Read through first - Understand the goal
2. Type the code - Don't copy-paste
3. Experiment - Modify and see what happens
4. Build your own - Apply concepts to your ideas

Getting Help

• Check the Language Reference
• See examples/ for working code
• Use the REPL to experiment

Happy building!