sequenceAsyncResult.md

Option.sequenceAsyncResult

Namespace: FsToolkit.ErrorHandling

Function Signature:

Async<Result<'a, 'e>> option -> Async<Result<'a option>, 'e>

Note that sequence is the same as traverse id. See also Option.traverseAsyncResult.

See also Scott Wlaschin's Understanding traverse and sequence.

Examples

Example 1

let r1 : Async<Result<int option, string>> =
  Some (async { return Ok 42 }) |> Option.sequenceAsyncResult 
// async { return Ok (Some 42) }

let r2 : Async<Result<int option, string>> =
  Some (async { return Error "something went wrong" }) |> Option.sequenceAsyncResult 
// async { return Error "something went wrong" }

let r3 : Async<Result<int option, string>> =
  None |> Option.sequenceAsyncResult 
// async { return Ok None }