Hello World

Write, run, and compile your first Turbo program.

Create a Source File

Create a file called hello.tb with the following content:

fn main() {
    print("Hello, world!")
}

Every Turbo program needs a main function as its entry point. The print function is a built-in that outputs to stdout.

Run with JIT

Use turbo run to compile and execute in a single step using the JIT compiler:

$ turbo run hello.tb
Hello, world!

The JIT (Just-In-Time) compiler uses Cranelift to compile your code to machine code in memory and runs it immediately. This is the fastest way to iterate during development.

Build a Native Binary

Use turbo build to compile to a standalone native executable:

$ turbo build hello.tb
$ ./hello
Hello, world!

AOT (Ahead-Of-Time) compilation produces a self-contained binary with no runtime dependencies. The binary is linked with a small C runtime for I/O and memory operations.

JIT vs AOT

A Slightly Bigger Example

fn abs(x: i64) -> i64 {
    if x < 0 { 0 - x } else { x }
}

fn clamp(val: i64, lo: i64, hi: i64) -> i64 {
    if val < lo { lo }
    else { if val > hi { hi } else { val } }
}

fn main() {
    assert(abs(-42) == 42)
    assert(clamp(150, 0, 100) == 100)
    print("All checks passed!")
}

Notice how if is an expression that returns a value -- no need for ternary operators or explicit return statements.