Srtp and Records.fs

    type Test =
        { EntityId: string }

    type Test2 =
        { EntityId: string
          Name: string 
          Length: int }

    let inline (|HasEntityId|) x =
        fun () -> (^a : (member EntityId: string) x)

    let inline entityId (HasEntityId f) = f()

    let inline (|HasName|) n =
        fun () -> (^a : (member Name: string) n)

    let inline name (HasName f) = f()
    let inline test2f (HasName n & HasEntityId id) = sprintf "name %s id %s" (n()) (id())
    let test2 = {Test2.EntityId = "123"; Name = "123"; Length = 2}
    let a = entityId { EntityId = "123" }
    let b = entityId test2
    let c = name test2
    let d = test2f test2