tachyon #

a brainfuck interpreter written in rust.

install #

pre-built binaries are available under tags.

download the archive for your platform, then:

# extract
tar xzf tachyon-<version>-<arch>.tar.gz

# (optional) move to somewhere on your PATH
mv tachyon ~/.local/bin/

archive	platform
tachyon-*-aarch64-apple-darwin.tar.gz	macOS (Apple Silicon)¹
tachyon-*-aarch64-linux-gnu.tar.gz	Linux (ARM64)²
tachyon-*-x86_64-linux-gnu.tar.gz	Linux (x86_64)²

¹ if macOS complains about not being able to open the binary due to lack of developer verification, run: xattr -d com.apple.quarantine path/to/tachyon

² linux builds are untested as of right now! you have been warned!

alternatively, build from source:

cargo build --release

usage #

tachyon path/to/your/script.bf [OPTIONS]

use wrapping data pointer and raw i/o:

tachyon script.bf -d wrap -u raw

use raw input and ascii output:

tachyon script.bf -d wrap -i raw -o ascii

set a custom tape size of 100 cells:

tachyon script.bf -l 100

crash on cell overflow instead of wrapping:

tachyon script.bf -c error

options #

flag	description	values
-d, --data-oob	data pointer out-of-bounds behavior	error (default), wrap
-c, --cell-oob	cell value out-of-bounds behavior	wrap (default), error
-l, --length	custom tape length	number (default: 30,000)
-i, --input-type	set input mode	ascii (default), raw
-o, --output-type	set output mode	ascii (default), raw
-u, --io-type	set both input and outtput	ascii (default), raw
-t, --trace	enable instruction tracing with optional delay in ms	default: false, 0

roadmap #

features and milestones! nothing is guaranteed to happen. less of a roadmap and more a list of things i'd like to do

this is all pretty overkill but im using this project as a way to learn stuff

cli #

• argument parsing: possibly switch to clap for nicer cli experience
• behavior flags: overrides defaults in code (& possibly eventually in config?)
  • set data pointer & cell value behavior
  • set custom tape size
• 8-bit i/o: add 8-bit input/output option alongside ascii default
  • monomorphization: implement input/output strategy for minor optimization gains
• config file: set up per-project config file for input & output

out-of-bounds behaviors #

• data pointer behavior
  • error (default): crash when moving past tape boundaries
  • wrap: going out of bounds wraps around to start/beginning
• cell value behavior
  • wrap (default): 0 - 1 = 255
  • error: crash on overflow/underflow

better diagnostics #

• errors: switch to miette for richer error display with source snippets
• tracing: cli flag to print state of vm/tape after every instruction

visualization #

• real-time cell visualization: tui showing tape being adjusted and data pointer moving in real time at adjustable speed
• wasm: compile to wasm for browser-based frontend?

debugging #

• step debugger: REPL-style debugger with breakpoints, cell inspection, and instruction stepping

maintenance #

• comprehensive testing: for all instructions and out-of-bounds behaviors
• benchmarking: use criterion to track performance?