[Feature Request] Add a Result type to `dart:core`

[rusty-snake]

I'm not going to outline the benefits of Result types in general here, you can find a lot resource in the internet (example).

Reasons why there should be a Result type in dart:core:

• Standardization: Currently there are around a dozen implementations for Result types on pub.dev. This is a very split ecosystem with bad interoperability, different APIs and users spend a lot time on choosing "the right" package. Including at least the core classes in dart:core would standardize the type/class giving interoperability. Packages can adopt these types/classes and add own extensions for more opinionated APIs.
• Easy access without extra package for simple usage.

[lrhn]

The current Dart-team provided Result type is in package:async. Use that.

If it's not good enough, how should it be changed? (I have singer ideas.)

If it's not discoverable enough, ... that could be an apartment for adding something to dart:async or similar.

It's one of those kinds of classes when there are many small details that can be varied, and we always risk making something slightly different from what people actually want.

(I have made a few variations based on extension types. That's another option.)

[rusty-snake]

The current Dart-team provided Result type is in package:async. Use that.

That are great news.

If it's not discoverable enough,

Yes

It's one of those kinds of classes when there are many small details that can be varied, and we always risk making something slightly different from what people actually want.
(I have made a few variations based on extension types. That's another option.)

Experimenting with new APIs in package:s before adding to dart: is good. If the core part of an new API is deemed good enough it is also possible move only this part to dart: and keep experimenting with convenience functions in package:.

[mackings]

Acknowledged.