repiet

I'm a lover of esoteric languages, and Piet[1] captured my imagination more than any other. So, I wrote a compiler[2] for the language, eventually writing a backend that re-targets Piet itself. And since I love code golf, I wrote most of the compiler in the extremely tortured form that only fellow golfers can love. But I balanced the golf with extensive comments, as a bit of an experiment on the varied advice that we programmers receive about comments. Do they help? Can I keep them current as the code beneath them changes? (Jury's still out on both, but I find the juxtaposition aesthetically amusing). Just recently, I made a friend! And by "friend" I mean that another human has written another Piet compiler[3] and it's a beautiful project and we were delighted to discuss our tortuous projects that we wrote for pure fun! So I've got

> What does an algorithm look like? Writing Piet by hand is a fun way to explore this. Sergei Lewis[1] and I[2] have each written tools to generate Piet code. Sergei's assembler makes much nicer looking code than my Piet backend. All you can really see from my compiler's output is that I'm really lazy and used a trampoline[3] [1] http://www.toothycat.net/wiki/wiki.pl?MoonShadow/Piet [2] https://github.com/boothby/repiet/ [3] https://en.wikipedia.org/wiki/Trampoline_(computing)

Sadly, that depends on a discrepency between npiet and the current Piet spec: > The interpreter now begins sliding from its current white codel, in the new direction of the DP, until it either enters a coloured block or encounters another restriction. The npiet interpreter, instead, rewinds its position to the last colored codel upon peeking through whitespace. One of these days, I intend to add that behavior as an option to the lexer in my Piet compiler[1], but I haven't bothered yet. Following the spec, the program is a trivial nonhalting loop because the extreme corners of almost all blocks are white-adjacent. Writing complex Piet programs to target multiple interpreters and compilers is quite the challenge, as they've all got subtly different undocumented interpretations of the spec. I think that the output of my Piet backend is m

I didn't know anything about compilers, but I figured out how to compile Piet programs, so I wrote a compiler[1]. The project has stalled out for (a) lack of free time and (b) some silly ambitions, but I don't care what the public thinks about my lack of updates, and that's great. In the meantime, I've been going down weird rabbit holes and learning aspects of computing that I missed in school. [1] https://github.com/boothby/repiet

Bears mentioning that Piet is "faster than C" if you use the right compiler. https://github.com/boothby/repiet/blob/master/README.md#but-... Among the esoteric languages I've learned, Piet is by far, hands down, my favorite. But it's curiously opinionated about reading input. I don't think any interpreter / compiler gets it right, mine included. Painting (one does not write) Piet code to safely handle input, by that spec, is particularly annoying.

Look what you made me do! https://github.com/boothby/repiet/#but-is-it-faster-than-c