Add Result.sequenceAsync

[demystifyfp]

Add Result.sequenceAsync

[TheAngryByrd]

Usually when I end up with that situation I haven't done something right. The functions all need to align to the expected output type which is Async<Result<Webhook, Error>>.

So for instance I would create some helpers do:

//looks like were missing some of these helper functions like AsyncResult.ofAsync or AsyncResult.ofResult
module AsyncResult=
  let ofAsync (a : Async<_>) = a |> Async.map Result.Ok
  let ofResult (r : Result<_,_>) = r |> Async.singleton

let createWebhook = Workflows.createWebhook  |> AsyncResult.ofAsync
let parseRequiredAttr x y = parseRequiredAttr x y |> AsyncResult.ofResult
let parseOptOptAttr x y = parseOptOptAttr x y |> AsyncResult.ofResult

Then in the implementation use the AsyncResult operators to do:

let! webhook =
  createWebhook
  <!> parseRequiredAttr a.callbackUrl WebhookCallbackUrl.TryCreate
  <*> parseOptOptAttr a.authorizationHeader WebhookAuthorizationHeader.TryCreate

The reason I'm loosely against this is because I've seen people just trying to make types fit without actually understanding what is going on. That said I could be totally wrong about this.

[cmeeren]

The operators I'm using are the Validation operators, and they are only available for Result.

Besides, is there a significant conceptual difference between using wrappers to make all the types match up up front (or as you go along and call them), versus transforming once at the end? The latter seems to be less work/verbose.

[TheAngryByrd]

The operators I'm using are the Validation operators, and they are only available for Result.

Looks like we should also add those for Async/Task/JobResult variants too :)

The latter seems to be less work/verbose.

Yeah, that is definitely a downside to the alternative I have given.

[cmeeren]

Looks like we should also add those for Async/Task/JobResult variants too :)

Would be great! In my specific case, I'd still want Result.sequenceAsync though, both due to being less boilerplate, and because it's confusing to have to switch back and forth between different operators.

[TheAngryByrd]

Make a PR 😄

[tamizhvendan]

@cmeeren The latest version 1.2.2 has your changes. Can you verify and close this issue?

[cmeeren]

It's there, thanks! 👍