Years ago, in the relatively early days of the Parrot project, I wrote an interpreter for the language hq9+ in Parrot Assembly.

Now that I'm learning Perl 6 and working on Perl 6 documentation, I figured this would be a relatively easy and enjoyable project to do in Perl 6.

hq9+ has four functions that do everything needed for computer science.

"h" prints "Hello, world!".

"q" prints a quine.

"9" prints out 99 bottles of beer on the wall.

"+" increments the accumulator.

There is also an object oriented extension of hq9+ called hq9++, but that's a project for another day.

ADDENDUM: Realized that I totally overengineered hq9plus.p6, so have refactored it into hq9plus-simpler.p6. Choices!