map2 - FsToolkit.ErrorHandling

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map2
JobResult.map2
Namespace: FsToolkit.ErrorHandling
Function Signature:
('a -> 'b -> 'c) -> Job<Result<'a, 'd>> -> Job<Result<'b, 'd>> 
  -> Job<Result<'c, 'd>>
Examples
Note: Many use-cases requiring map operations can also be solved using the jobResult computation expression.
Example 1
Given the functions
getFollowerIds : UserId -> Job<Result<UserId, exn>>
createPost : CreatePostRequest -> Job<Result<PostId, exn>>
And the type
type NotifyNewPostRequest = 
  { UserIds : UserId list
    NewPostId : PostId }
  static member Create userIds newPostsId =
    {UserIds = userIds; NewPostId = newPostsId}
We can create a NotifyNewPostRequest using JobResult.map2 as below:
let createPostAndGetNotifyRequest (req : CreatePostRequest) = 
  //  Job<Result<UserId, exn>>
  let getFollowersResult = getFollowerIds req.UserId
​
  // Job<Result<PostId, exn>>
  let createPostResult = createPost req
​
  // Job<Result<NotifyNewPostRequest, exn>>
  let newPostRequestResult =
    JobResult.map2 
      NotifyNewPostRequest.Create getFollowersResult createPostResult
​
  // ...
map
map3
Last modified 9mo ago
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Outline
JobResult.map2
Examples