Eg they can't distinguish between one or two layers of nullable. Or between null and an optional null.
(In eg Rust syntax between `Option<Option<MyType>>` vs `Option<MyType>`. Or `()` vs `Option<()>`, where `()` would be how you spell `null` in Rust.)
Using tags is simpler and cleaner.
Eg they can't distinguish between one or two layers of nullable. Or between null and an optional null.
(In eg Rust syntax between `Option<Option<MyType>>` vs `Option<MyType>`. Or `()` vs `Option<()>`, where `()` would be how you spell `null` in Rust.)
Using tags is simpler and cleaner.