Enum Result
A Result is an Option that allows the error case to have a value, typically an error message.
enum Result[A, B]
{
Failure(A),
Success(B)
}
define failure: Option[A]
If self is Success, returns None.
Otherwise, this returns Some(A).
define is_failure: Boolean
Return true if self is Failure, false otherwise.
define is_success: Boolean
Return true if self is Success, false otherwise.
define success: Option[B]
If self is Succcess, returns Some(B).
Otherwise, this returns None.