FsToolkit.ErrorHandling
  • README
  • FsToolkit.ErrorHandling
    • Result
      • apply
      • bind
      • check
      • Computation Expression
      • either Functions
      • fold
      • ignore
      • map
      • map2
      • map3
      • mapError
      • Operators
      • orElse Functions
      • Other Functions
      • require Functions
      • tee Functions
      • tryCreate
      • zip
      • zipError
      • Lists
        • traverseResultM
        • sequenceResultM
        • traverseResultA
        • sequenceResultA
      • Sequences
        • traverseResultM
        • sequenceResultM
        • traverseResultA
        • sequenceResultA
      • Transforms
        • ofChoice
    • Option
      • bind
      • bindNull
      • Computation Expression
      • either
      • map
      • map2
      • map3
      • sequenceAsync
      • sequenceResult
      • sequenceTask
      • sequenceTaskResult
      • tee Functions
      • traverseAsync
      • traverseResult
      • traverseTask
      • traverseTaskResult
      • zip
      • Lists
        • traverseOptionM
        • sequenceOptionM
        • traverseVOptionM
        • sequenceVOptionM
      • Sequences
        • traverseOptionM
        • sequenceOptionM
        • traverseVOptionM
        • sequenceVOptionM
      • Transforms
        • ofNull
        • ofPair
        • ofResult
        • ofValueOption
        • toValueOption
    • ResultOption
      • apply
      • bind
      • Computation Expression
      • ignore
      • map
      • map2
      • map3
      • mapError
      • Operators
      • zip
      • zipError
      • Transforms
        • ofChoice
        • ofOption
        • ofResult
    • AsyncResult
      • apply
      • bind
      • check
      • Computation Expression
      • error
      • foldResult
      • ignore
      • map
      • map2
      • map3
      • mapError
      • Operators
      • Other Functions
      • zip
      • zipError
      • List
        • traverseAsyncResultM
        • sequenceAsyncResultM
        • traverseAsyncResultA
        • sequenceAsyncResultA
      • Sequences
        • traverseAsyncResultM
        • sequenceAsyncResultM
        • traverseAsyncResultA
        • sequenceAsyncResultA
      • Transforms
        • ofAsync
        • ofResult
        • ofTask
        • ofTaskAction
    • AsyncOption
      • apply
      • bind
      • Computation Expression
      • either
      • map
      • orElse Functions
      • Other Functions
    • AsyncResultOption
      • apply
      • bind
      • Computation Expression
      • ignore
      • map
      • map2
      • map3
      • Operators
      • Transforms
        • ofAsyncOption
        • ofAsyncResult
        • ofOption
        • ofResult
    • Task
      • apply
      • bind
      • bindV
      • catch
      • Computation Expression
      • ignore
      • map
      • mapV
      • map2
      • map3
      • zip
      • Transforms
        • ofUnit
    • TaskOption
      • apply
      • bind
      • Computation Expression
      • either
      • map
      • Other Functions
      • zip
    • TaskResult
      • apply
      • bind
      • check
      • catch
      • Computation Expression
      • ignore
      • map
      • map2
      • map3
      • mapError
      • Operators
      • Other Functions
      • error
      • zip
      • zipError
      • Lists
        • traverseTaskResultM
        • sequenceTaskResultM
        • traverseTaskResultA
        • sequenceTaskResultA
      • Transforms
        • ofAsync
        • ofResult
        • ofTask
    • TaskResultOption
      • apply
      • bind
      • Computation Expression
      • ignore
      • map
      • map2
      • map3
      • Operators
    • Validation
      • apply
      • Computation Expression
      • error
      • map
      • map2
      • map3
      • mapError
      • mapErrors
      • Operators
      • zip
      • Transforms
        • ofChoice
        • ofResult
    • AsyncValidation
      • apply
      • Computation Expression
      • error
      • map
      • map2
      • map3
      • mapError
      • mapErrors
      • Operators
      • zip
      • Transforms
        • ofChoice
        • ofResult
    • TaskValidation
      • apply
      • Computation Expression
      • error
      • map
      • map2
      • map3
      • mapError
      • mapErrors
      • Operators
      • zip
      • Transforms
        • ofChoice
        • ofResult
  • FsToolkit.ErrorHandling.AsyncSeq
    • AsyncSeq
      • Computation Expression
  • FsToolkit.ErrorHandling.IcedTasks
    • CancellableTaskResult
      • apply
      • bind
      • Computation Expression
      • getCancellationToken
      • map
      • Operators
      • Other Functions
      • zip
      • parallelZip
    • CancellableTaskValidation
      • apply
      • bind
      • Computation Expression
      • error
      • getCancellationToken
      • map
      • map2
      • map3
      • mapError
      • mapErrors
      • Operators
      • zip
      • parallelZip
      • Transforms
        • ofChoice
        • ofResult
  • FsToolkit.ErrorHandling.JobResult
    • Job
      • apply
      • map2
      • map3
      • singleton
      • zip
    • JobOption
      • apply
      • bind
      • ce
      • either
      • map
    • JobResult
      • apply
      • bind
      • catch
      • Computation Expression
      • error
      • fromTask
      • fromUnitTask
      • ignore
      • map
      • map2
      • map3
      • mapError
      • Operators
      • Other Functions
      • zip
      • zipError
      • Lists
        • traverseJobResultM
        • sequenceJobResultM
        • traverseJobResultA
        • sequenceJobResultA
      • Transforms
        • ofAsync
        • ofJob
        • ofResult
        • fromTask
        • fromUnitTask
    • JobResultOption
      • apply
      • bind
      • Computation Expression
      • ignore
      • map
      • map2
      • map3
  • General Docs
    • Bind Mappings
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  • AsyncValidation Computation Expression
  • Examples
  1. FsToolkit.ErrorHandling
  2. AsyncValidation

Computation Expression

PreviousapplyNexterror

Last updated 1 year ago

AsyncValidation Computation Expression

Namespace: FsToolkit.ErrorHandling

The AsyncValidation type is defined as:

type AsyncValidation<'a,'err> = Async<Result<'a, 'err list>>

This CE can take advantage of the to join multiple error results into a list.

Examples

See for other validation-like examples

// Result<string, string> -> Async<Result<string, string>>
let downloadAsync stuff = async {
    return stuff
}

// AsyncValidation<string, string>
let addResult = asyncValidation {
  let! x = downloadAsync (Ok "I")
  and! y = downloadAsync (Ok "am")
  and! z = downloadAsync (Ok "async!")
  return sprintf "%s %s %s" x y z
}
// async { return Ok "I am async!" }

// AsyncValidation<string, string>
let addResult = asyncValidation {
  let! x = downloadAsync (Error "Am")
  and! y = downloadAsync (Error "I")
  and! z = downloadAsync (Error "async?")
  return sprintf "%s %s %s" x y z
}

// async { return Error [ "Am"; "I"; "async?" ] }
and! operator
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