Hello World

Your First Program

Create a file called hello.vx and add the following:

fn main():
    print("Hello, World!")

Run it with:

vexel run hello.vx

Output:

Hello, World!

Understanding the Structure

The main function

Every Vexel program must have a main function. It is the entry point — execution starts there. The function takes no parameters and returns nothing.

fn keyword

fn declares a function. The colon at the end of the signature opens the function body. The body is indented with four spaces.

Indentation

Vexel uses indentation — not curly braces — to define code blocks. The standard indent is 4 spaces. Mixing tabs and spaces will produce a parse error.

print

print is a built-in function that writes a value to standard output followed by a newline. It accepts any type — int, float, str, or bool.

Compiling to a Native Binary

vexel run JIT-compiles and executes immediately. To produce a standalone binary:

# compile to hello.exe (Windows) or hello (Linux/macOS)
vexel compile hello.vx -o hello

# run the binary directly
./hello

The compiled binary has no dependency on Vexel or Python. It links only the small Vexel garbage-collected runtime which is embedded automatically.

Comments

Vexel supports single-line comments starting with #. Everything after the # on that line is ignored by the compiler.

# This is a comment
fn main():
    # print outputs to stdout
    print("Hello")  # inline comment