if line.level < 0 || line.level >= bits.UintSize-2 || line.index < 0 || line.index<<line.level != v.end {
return nil, fmt.Errorf("view line (%d, %d) does not start at message %d", line.level, line.index, v.end)
}
if line.level < 0 || line.level >= bits.UintSize-2 || line.index < 0 || line.index<<line.level != v.end {
return nil, fmt.Errorf("view line (%d, %d) does not start at message %d", line.level, line.index, v.end)
}