apply

Namespace: FsToolkit.ErrorHandling

Function Signature:

Async<('a -> 'b) option> -> Async<'a option> 
  -> Async<'b option>

Examples

Take the following function for example

// string -> int
let characterCount (s: string) = s.Length

Example 1

let result =
    AsyncOption.some "foo" // Async<string option>
    |> AsyncOption.apply (AsyncOption.some characterCount) // Async<int option>

// async { Some 3 }

Example 2

let result =
    Async.singleton None // Async<string option>
    |> AsyncOption.apply (AsyncOption.some characterCount) // Async<int option>

// async { None }

Example 3

let result : Async<int option> =
    AsyncOption.some "foo" // Async<string option>
    |> AsyncOption.apply (Async.singleton None) // Async<int option>

// async { None }