let's allow FS3245 for this scenario

[Xyncgas]

Seq.fold(fun state i -> {|state with a = 0|}) {|b = 0|}

It currently generates a compiler error FS3245

if we can allow this and we modify the code a little bit

let compile magic =
    magic () |> Seq.fold(fun state i -> (snd i) (fst i) state) struct {|b = 0|}

makes writing UI description like these possible

let labels_and_map =
    [|
        "UserName", (fun input state -> struct {|state with usr= input|}
        "PassWord", (fun input state -> struct {|state with pwd= input|}
    |]

let result = labels_and_map |> compile magic
//result :struct {|usr : string; pwd : string|}

usefulness : imagine you could write beautiful UI using a template and all you have to provide to the template is stuff like this
ps : the fsharp foundation has a project called fsharp.interop.dynamic, it can do similar thing https://github.com/fsprojects/FSharp.Interop.Dynamic

If I can use FS3245 I don't have to use dynamic

[Xyncgas]

Related : #1313