Szer

open System.Text
open Microsoft.FSharp.Reflection

let printDu du =
    
    let rec inner (builder: StringBuilder, duValue: obj, duType: Type) =
        
        if not (FSharpType.IsUnion duType) then failwith "FU!"
              
        let case, values = FSharpValue.GetUnionFields(duValue, duType)