[cjhanks]

A 'primitive type' is one which can be directly operated on by intrinsic CPU instructions. My understanding of Scala was that all objects (such as Long, Int...) are encapsulated inside of an object.

Therefore an array of boxed types will not be memory aligned; and any vector instructions (which are very important to scientific computing) cannot be used.

Perhaps something has changed in Scala land since I last looked(??).

[premium-concern]

No, it has been worked the way GP wrote since approximately forever.