> For the complete documentation index, see [llms.txt](https://demystifyfp.gitbook.io/fstoolkit-errorhandling/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://demystifyfp.gitbook.io/fstoolkit-errorhandling/fstoolkit.errorhandling/taskresultoption/map.md).

# map

### TaskResultOption.map

Namespace: `FsToolkit.ErrorHandling`

Function Signature:

```fsharp
('a -> 'b) -> Task<Result<'a option, 'c>> 
  -> Task<Result<'b option, 'c>>
```

### Examples

Note: Many use-cases requiring `map` operations can also be solved using [the `taskResultOption` computation expression](/fstoolkit-errorhandling/fstoolkit.errorhandling/taskresultoption/ce.md).

#### Example 1

Given the function

```fsharp
getUserById : UserId -> Task<Result<User option, exn>>
```

Then using the `TaskResultOption.map` we can get the name of the user like this:

```fsharp
// Task<Result<PersonName option>, exn>
getUserById sampleUserId
|> TaskResultOption.map (fun user -> user.Name)
```