Stack unwinder

ghetto-tco.js

function tco(f) {
  let isin = false;
  return function() {
    if (isin) throw [this, arguments];
    isin = true;
    let args = [this, arguments];
    while(true) {
      try {
        const ret = f.apply(args[0], args[1]);
        isIn = false;
        return ret;
      } catch(e) {
        args = e;
      }
    }
  }
};

// example
function sum(s) {
  const sub = tco((i, acc) => {
    if (i >= s.length) return acc;
    return sub(i + 1, acc + s[i]);
  });
  return sub(0, 0);
};