code: function createReader(noDecode, type) {
    if (noDecode) {
      return (function (skipper) {
        return function (tap) {
          var pos = tap.pos;
          skipper(tap);
          return tap.buf.slice(pos, tap.pos);
        };
      })(type._skip);
    } else {
      return function (tap) { return type._read(tap); };
    }
  }
docs: Create bytes consumer, either reading or skipping records.