in src/primitives.rs [261:275]
fn deserialize<R: std::io::Read>(
reader: &mut R,
version_map: &VersionMap,
app_version: u16,
) -> VersionizeResult<Self> {
let option = u8::deserialize(reader, version_map, app_version)?;
match option {
0u8 => Ok(None),
1u8 => Ok(Some(T::deserialize(reader, version_map, app_version)?)),
value => Err(VersionizeError::Deserialize(format!(
"Invalid option value {}",
value
))),
}
}