orElse method
Returns a Some of the original value if this
is a Some, or the result of
calculateOther
otherwise.
Examples
// prints "Some(2)"
print(const Some(2).orElse(() => const Some(3)));
// prints "Some(3)"
print(const None<int>().orElse(() => const Some(3)));
Implementation
@override
@useResult
Some<T> orElse(Option<T> Function() calculateOther) => this;