Hello World!

Let's start by learning how to create a simple Hello World program!

Start by creating a new file named helloworld.lo anywhere on your computer.

In Steplo, all programs need to have a single main procedure, located anywhere within the source code. A main procedure can be declared as follows:

main || {

}

All of the code to be executed when the program starts goes in the body of the main procedure, which is surrounded by braces. Let's try calling the built-in out function to print to stdout:

main || {
    out("Hello world!");
}

Now we can compile this program! The compiled Scratch program can be written to any directory on your system, specified by the compile command. In this example, we'll use a directory named out. To compile, we can then call:

cargo run helloworld.lo out --target scratch

This will create helloworld.s.sb3 inside of out, which we can load into Scratch to see our working program!