bind.md

Option.bind

Namespace: FsToolkit.ErrorHandling

Function Signature

('TInput -> 'TOutput option) -> 'TInput option -> 'TOutput option

Examples

Take the following function for example

// string -> int option
let tryParseInt (s: string) =
    match Int32.TryParse(s) with
    | true, i -> Some i
    | false, _ -> None

Example 1

let opt : int option =
    Some "123" // string option
    |> Option.bind tryParseInt // int option

// Some 123

Example 2

let opt : int option =
    Some "Not a number" // string option
    |> Option.bind tryParseInt // int option

// None

Example 3

let opt : int option =
    None // string option
    |> Option.bind tryParseInt // int option

// None