Jottary

Jottary (pronounced /dʒɑteri/) is a unary Turing tarpit and an even better Gödel-numbering than its sister language Jot.

Read my blog post for more information.

This project is basically just a slightly modified version of birb.

Performance

The bruijn implementation:

$ hyperfine "printf '1%.0s' {1..503} | bruijn -y jottary.bruijn"
    Time (mean ± σ):     756.4 ms ±  35.2 ms    [User: 1816.9 ms, System: 1735.2 ms]
    Range (min … max):   706.9 ms … 808.2 ms    10 runs

This implementation:

$ hyperfine "jottary reduce <(printf '1%.0s' {1..503})"
  Time (mean ± σ):      10.8 ms ±   0.7 ms    [User: 1.7 ms, System: 9.0 ms]
  Range (min … max):     9.5 ms …  12.5 ms    163 runs

🚀 incredible!! 🎉

Transpiler

The transpiler converts binary lambda calculus to Jottary. It does this by converting to SKI combinators, then to Jot, and finally to Jottary. Aside from general inefficiency of LC-SKI conversion, the jottary programs will grow exponentially compared to its Jot variant. For example, the id program 0010 gets transpiled to 2089884 unary symbols (260KB!).

Usage

Install Haskell's stack. Then,

• stack run -- reduce file.jottary or stack run -- reduce <(echo 1111111)
• stack run -- transpile <(echo 0010) to transpile the id program
• stack install so you can enjoy jottary from anywhere