Values serialization: optional `Type`s `None` value can't be serialized / deserialized
Value
can host None
values for some Type
s. Current implementation of Value
ser / de always assume the value is Some
and ser unwrap
s the underlying value before generating the representation.
The serialized representation should represent optional Type
s as Option
s and the Type
s implementing FromValue
as the actual type.
Edited by François Laignel