result_class

Description:

result class

Result #
A class that for transparent error propagation and handling similar to Rusts result
You can do computations with values without having to check for validity with the map-method.
final r = const Result<int, String>.ok(2);
final r1 = r.map((value) => value * 2);
assert(r1.contains(4));
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It's also possible to flatMap a function that returns a Result over the value to prevent nesting of [Result]s
Result<int, String> failable(int i) => i > 5
? const Result.err("Some error happened")
: Result.ok(i * 2);

final s = const Result<int, String>.ok(10);
final s1 = s.flatMap(failable);
assert(s1.containsErr("Some error happened"));
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mapErr and flatMapErr provide equivalent functionality for errors.