A small utility function to map from Godel numbering into Typographical Number Theory (for GEB readers)

godel2tnt.js

const table = {
  666: "0",
  123: "S",
  111: "=",
  112: "+",
  236: " x ",
  362: "(",
  323: ")",
  212: "<",
  213: ">",
  312: "[",
  313: "]",
  262: "a",
  163: "'",
  161: " ^ ",
  616: " v ",
  633: " -> ",
  223: "~",
  333: "∃",
  626: "∀",
  611: "punc."
}

/** @param {Array<number>} godelNumber */
const stringifyGodelNumber = (godelNumber) => {
  if (!Array.isArray(godelNumber)) {
    throw new TypeError("Input must be an array of numbers.");
  }

  return godelNumber.map(num => {
    const str = table[num];
    if (!str) {
      throw new Error(`Godel number ${num} not found in table.`);
    }

    return str;
  }).join("");
}

(() => {
  const before = stringifyGodelNumber([
    // 362, 262, 112, 262, 163, 323, 111, 123, 123, 123, 123, 666
    223, 362, 262, 236, 262, 323, 111, 262, 163
  ]);

  const after = stringifyGodelNumber([
    // 362, 123, 123, 666, 112, 123, 123, 123, 666, 323, 111, 123, 123, 123, 123, 666
    223, 362, 123, 666, 236, 123, 666, 323, 111, 262, 163
  ]);

  console.log("Before:", before);
  console.log("After:", after);
})();