Hello, world

Your first Raku program runs right here on this page — edit it and run it again.

Welcome to the tour. Every code block you'll see is a small working program, running in your browser — nothing to install, nothing sent to a server. This one has already run:

say 'Hello, World!';

Hello, World!

Click into the code, change the text, and press Run (or Ctrl-Enter). The output updates instantly.

say and print #

say prints its arguments followed by a newline. print does the same without the newline. say is what you'll use most.

print 'Hello, ';
print 'World';
say '!';
say 40 + 2;

Hello, World!
42

As you can see, say is happy to print numbers too — and evaluates any expression you give it.

Comments #

Anything from # to the end of the line is a comment.

# This line does nothing.
say 'But this one runs.';   # ...and this comment is ignored

But this one runs.

Try it #

Make this program greet Raku instead of shouting into the void.

# Print: Hello, Raku!

When you're ready, use the Next button below (or the → key) to continue.