unwrap method
T
unwrap()
Returns the success value, or throws a ResultException if this is Err.
Result.ok(42).unwrap(); // 42
Result.err('bad').unwrap(); // throws ResultException
Implementation
T unwrap() {
if (isOk) return (this as Ok<T, E>).value;
throw ResultException((this as Err<T, E>).error);
}