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Quickstart

Hello, world

Create hello.kod:

func main() -> int64 {
    print("Hello, world!")
    return 0
}

Build and run:

$ uv run kod build hello.kod
$ ./build/apps/hello/hello
Hello, world!

uv run kod run hello.kod does both in one step.

A real program

func greet(anon name: str) -> none {
    print(f"Hello, {name}!")
}

func main() -> int64 {
    let names: [str] = ["Alice", "Bob", "Carol"]
    for name in names {
        greet(name)
    }
    return 0
}

Variables

Bindings are declared with let and are immutable — the name can't be reassigned. A type annotation is usually required:

let x: int64 = 42
let s: str = "hello"
let flag: bool = true

For a binding you intend to reassign, use mut:

mut count: int64 = 0
count = count + 1   // ok

let limit: int64 = 10
limit = 20          // error: cannot reassign immutable binding `limit`

A test file

// arithmetic_test.kod
test "addition" {
    assert 2 + 2 == 4
}

test "subtraction" {
    assert 10 - 3 == 7
}

$ uv run kod test arithmetic_test.kod
ok   addition
ok   subtraction

2/2 passed

Next steps