in packed.go [133:146]
func (p packed) WriteTo(stream io.Writer) (n int64, err error) {
h := packedHeader{
Bits: uint64(p.bits),
Size: p.size,
Version: qfBitPackedVectorVersion,
}
if err = binary.Write(stream, binary.LittleEndian, h); err != nil {
return
}
n, err = writeUintSlice(stream, p.space)
// is this correct?
n += int64(unsafe.Sizeof(h))
return
}