(Changed in version 2.8.0) keys returns Iterable[A] rather than Iterator[A].
(Changed in version 2.9.0) The behavior of scanRight has changed. The previous behavior can be reproduced with scanRight.reverse.
(Changed in version 2.9.0) transpose throws an IllegalArgumentException if collections are not uniformly sized.
(Changed in version 2.8.0) values returns Iterable[B] rather than Iterator[B].
(Since version ) see corresponding Javadoc for more information.
A double-backed map class that initially stores its elements in a
scala.collection.immutable.Map, but copies all data to ascala.collection.mutable.HashMapwhen many accesses are taking place (since the mutable map enables faster access than the immutable map).