code: func (l binaryFreeList) PutUint8(w io.Writer, val uint8) error {
  	buf := l.Borrow()[:1]
  	buf[0] = val
  	_, err := w.Write(buf)
  	l.Return(buf)
  	return err
  }
docs: // PutUint8 copies the provided uint8 into a buffer from the free list and
  // writes the resulting byte to the given writer.