Whenever I used to get the Scala REPL warning message, "There were deprecation warnings, re-run with -deprecation", I used to have to restart the REPL with the
-deprecation flag to see the warning message, like this:
$ scala -deprecation
That works, but sadly, you had to lose your entire REPL session to run it.
Thanks to the Scala gods, this is no longer necessary in Scala 2.10 (and newer). Now, when you get the REPL deprecation warning message, like this: