Incorrect formatting of function parameter application with lambdas

[nojaf]

Issue created from fantomas-online

Code

let printListWithOffset a list1 =
    List.iter
        (fun elem -> printfn "%d" (a + elem))
        list1

// OK if lambda body is long enough
let printListWithOffset a list1 =
    List.iter
        (fun elem ->
            // OK if lambda body is long enough
            printfn "%d" (a + elem))
        list1

Result

let printListWithOffset a list1 =
    List.iter (fun elem -> printfn "%d" (a + elem)) list1

// OK if lambda body is long enough
let printListWithOffset a list1 =
    List.iter (fun elem ->
        // OK if lambda body is long enough
        printfn "%d" (a + elem)) list1

Problem description

This example is taken from the Microsoft F# code formatting guidelines.
The style guide says that the lambda should be on the next line, while Fantomas keeps it on the same line as List.iter.

Extra information

• The formatted result breaks by code.
• The formatted result gives compiler warnings.
• I or my company would be willing to help fix this.

Options

Fantomas Master at 10/23/2020 14:47:21 - cda111e

Default Fantomas configuration