fun

A collection of scripts and mini-projects, hopefully a few will become something meaningful. See the rundown section for a description of what's in this repo. To run something locally, see the dependencies section. Everything here is licensed under the MIT License. For in-browser demos using codespaces, see demos

rundown:

• autodiff.scm is a short automatic differentiation library with a repl. Its whole thing is being able to evaluate derivatives at a point, but the derivatives it prints out are in s-exps and can't be further manipulated. To get started, once in the program's repl, run the :h command.
• mips-programs is currently just one mips program (mergesort), because I can't share the other one as it was a class assignment. I use them to test the mips vm.
• mips-c-vm is a virtual machine for a subset of MIPS. A usage example is in the Makefile (in the folder, make mergesort). It can run programs that write to a 256x512 display that starts at the address where .data starts: 0x10010000. Currently, the display is only functional on non-nix compilations, so one needs to install SDL2 normally.

demos:

Create a codespace based on this repo instructions. Then, run bash demo.sh <DEMO> in the terminal.

Available demos:

• autodiff. This will run the autodiff repl.
• vm-mergesort. This will run assemble mergesort.asm, then run it with the mips-c-vm.

dependencies:

• autodiff.scm is R5RS compliant except for its use of #!eof. I run it with Chicken Scheme. Gambit Scheme is also a fantastic option, and it has a web version, though it makes the autodiff repl look weird, so it needs the following patch:

;; Patch for running on try.gambitscheme.org
;; Replace the readrepl function with this one.
(define (readrepl)
  (display ">> ")
  (flush-output-port) ; flush port to make sure the prompt is displayed
  (read))

• mips-programs just needs Mars
• mips-c-vm The VM itself needs gcc, pkg-config, and SDL2. The whole experience requires Chicken Scheme (for the joke of an assembler) and Mars as well. Chibi Scheme also works.