Breaking all the rules

In most of my programming, I try and remain professional, and do things in a readable, maintainable way, that doesn't involve pushing the language to breaking point.

But, occasionally, I give myself free reign. What if you didn't care about the programmer who came after you? What if you didn't care about what a programmer should do in a certain circumstance?

For myself, over the years I've written and rewritten a C library, I like to call CNoEvil. Here's a little taste of what you could do:

#define EVIL_IO
#define EVIL_COROUTINE
#include "evil.h"

proc(example, int)
  static int i = 0;
  coroutine();
  While 1 then
    co_return(++i);
  end
  co_end();
  return i;
end

Main then
  displayln(example());
  displayln(example());
end

(And yes, that compiles. Without warnings. Even with -Wpedantic.)

So... Here's the challenge:

Ignoring the rules, and best practices... How can you take your favourite programming language... And make it completely unrecogniseable?

(Might be best to choose a language with macros, like Nim, Rust, any of the Lisps. Though, you can still do some impressively awful things in Java or Python, thanks to overloading inbuilt classes.)

Challenge Ideas:

• Make Python look like C
• Make Java look like Python
• Make anything look like BrainFuck

I don’t know how to really explain my fascination with programming, but I’ll try. To somebody who does it, it’s the most interesting thing in the world. It’s a game much more involved than chess, a game where you can make up your own rules and where the end result is whatever you can make of it. - Linus Torvalds