This member is added by an implicit conversion from CallbackBridge[T] to
any2stringadd[CallbackBridge[T]] performed by method any2stringadd in scala.Predef.
This member is added by an implicit conversion from CallbackBridge[T] to
StringFormat[CallbackBridge[T]] performed by method StringFormat in scala.Predef.
(Since version 2.0) Do not use this directly, use subclasses of this