checkCopyBag = (b, check) => {
  if (copyBagMemo.has(b)) {
    return true;
  }
  const result =
    ((passStyleOf(b) === 'tagged' && getTag(b) === 'copyBag') ||
      check(false, X`Not a copyBag: ${b}`)) &&
    checkBagEntries(b.payload, check) &&
    checkKey(b.payload, check);
  if (result) {
    copyBagMemo.add(b);
  }
  return result;
}
@param {any} b
@param {Checker} check
@returns {boolean}