bux-lang/README.md

Bux Programming Language

Status: Self-hosting phase — buxc2 (Bux compiler written in Bux) compiles .bux files to C. Bootstrap compiler (buxc, Nim) maintains backward compatibility.

Bux is a fast, compiled, strongly-typed systems programming language inspired by Rux. The long-term goal is a self-hosted compiler with a minimal runtime, native x86-64 backend, and modern tooling.

Bux improves on Rux with a richer standard library (Map, String), modern error handling (Result, Option, and the ? operator), and a portable C transpiler backend that runs on Linux, macOS, and Windows.

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Quick Start

# Build the bootstrap compiler (Nim)
make build

# Create a new project
bux new hello
cd hello

# Build and run
bux run

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Syntax Preview

Hello World

import Std::Io::PrintLine;

func Main() -> int {
    PrintLine("Hello, Bux!");
    return 0;
}

Error Handling with ?

enum Result {
    Ok(int),
    Err(String)
}

func Divide(a: int, b: int) -> Result {
    if b == 0 {
        return Result_NewErr("division by zero");
    }
    return Result_NewOk(a / b);
}

func Compute() -> Result {
    let x: int = Divide(10, 2)?;  // auto-propagates Err
    let y: int = Divide(x, 5)?;
    return Result_NewOk(y);
}

Structs and Methods

struct Rectangle {
    width: int;
    height: int;
}

extend Rectangle {
    func Area(self: Rectangle) -> int {
        return self.width * self.height;
    }
}

func Main() -> int {
    let rect: Rectangle = Rectangle { width: 10, height: 5 };
    PrintInt(rect.Area());
    return 0;
}

Generics

func Max<T>(a: T, b: T) -> T {
    if a > b {
        return a;
    }
    return b;
}

func Main() -> int {
    let m: int = Max<int>(10, 20);
    PrintInt(m);
    return 0;
}

Async/Await

import Std::Io::{PrintLine, PrintInt};

async func Compute() -> int {
    PrintLine("Compute: step 1");
    bux_async_yield();
    PrintLine("Compute: step 2");
    return 42;
}

func Main() -> int {
    let h1 = spawn Compute();
    let r1: int = h1.await as int;
    PrintInt(r1);
    return 0;
}

Hash Map

import Std::Map::{Map, Map_New, Map_Set, Map_Get};

func Main() -> int {
    let m: Map = Map_New(16);
    Map_Set(&m, "answer", 42);
    PrintInt(Map_Get(&m, "answer"));
    return 0;
}

---

Features

Feature	Status
Types	Primitives, pointers, slices, tuples, structs, enums, unions
Generics	Generic functions (monomorphization)
Algebraic Enums	Enums with data (Result, Option)
Pattern Matching	match with guards
Methods	extend blocks for struct methods
Interfaces	interface + extend for trait-like behavior
Error Handling	Result<T,E>, Option<T>, and the ? operator
Standard Library	Io, Array, String, Map
Backend	C transpiler (bootstrap) → self-hosting target
Gradual Ownership	@[Checked] + &T/&mut T borrow checking
Async/Await	async func, spawn, .await with stackful coroutines
Concurrency	Task/Channel (pthread-based), bux_async_yield/spawn
CTFE	const func — compile-time function execution
Trait Bounds	func Max<T: Comparable>(a: T, b: T) -> T
Package Manager	bux add, bux install, bux.lock, path + git deps
Tooling	bux new, bux build, bux run, bux check

---

Project Structure

bux/
├── src/              # Bootstrap compiler (Nim)
├── src_bux/          # Self-hosting compiler source (Bux)
├── _selfhost/        # Self-hosting build artifacts
├── stdlib/           # Standard library (.bux + .c runtime)
├── examples/         # Example programs
├── tests/            # Unit tests (Nim)
├── docs/             # Documentation
├── README.md
├── PLAN.md           # Roadmap to self-hosting
└── Makefile

---

Build & Test

# Build bootstrap compiler (Nim)
make build

# Build self-hosted compiler (Bux → C → binary)
make selfhost

# Run all tests
make test

# Run example programs
make test-examples

# Clean build artifacts
make clean

---

Documentation

• docs/LanguageRef.md — Language reference
• docs/Stdlib.md — Standard library documentation
• docs/BuildAndTest.md — Build and test guide
• PLAN.md — Roadmap to self-hosting

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License

MIT