Register F# DU (Discriminated Union) cases as event types in Marten event store

EventStore.fs

module EventStore =
    open Marten
    open Microsoft.FSharp.Reflection
    open System.Reflection
    
    type Events =
        | Event1 of string
        | Event2 of int

    let registerUnionCasesAsEvents<'a> (opts: StoreOptions) =
        typedefof<'a>.GetNestedTypes(BindingFlags.Public ||| BindingFlags.NonPublic)
        |> Array.filter FSharpType.IsUnion
        |> Array.iter opts.Events.AddEventType
    
    let getStore connectionString schemaName = DocumentStore.For (fun opts ->
        opts.Connection(connectionString)
        opts.DatabaseSchemaName <- schemaName
        opts.AutoCreateSchemaObjects <- AutoCreate.All
        opts |> registerUnionCasesAsEvents<Events>
    )