CastTxnFormat
trait CastTxnFormat[T <: Txn[T], Repr <: ([~ <: Txn[~]] =>> Writable)] extends WritableFormat[T, Repr[T]]
trait WritableFormat[T, Repr[T]]
trait TFormat[T, Repr[T]]
trait Writer[Repr[T]]
trait TReader[T, Repr[T]]
class Object
trait Matchable
class Any