It's trivial to store a null pointer in an Option::Some().
struct Foo;
fn main() {
let option_with_null: Option<*const Foo> = Some(std::ptr::null());
dbg!(option_with_null);
dbg!(option_with_null.is_none());
}
[src/main.rs:6] option_with_null = Some(
0x0000000000000000,
)
[src/main.rs:7] option_with_null.is_none() = false
As the creator of the function, you should try to adhere to the conventions and not try to break them.
Some(null) is not a valid result.
The whole point of the Option type is to let you know:
a) we got a result: Some(value)
b) there is no result: None