Deeplearning4j: Support to Scala 2.12

[napgab]

Would be great have a version of ScalNet already compiled for scala 2.12

[Charele]

I think it's not important,
the newest Spark only support Scala2.11, not 2.12 yet

[napgab]

You're right, but there is also who use DL4J with scala without spark, and i think that this project should be compatible with spark, but should not depends on it.

Scala 2.11 is not supported anymore, no more release are planned for 2.11.x.
Also Scala 2.12 is near the end of its roadmap, for this version are planned only eventually bug fixes.
https://github.com/scala/scala/milestones

It's time to upgrade! :)

[raver119]

cc @maxpumperla

[Charele]

Hi,I know ScalNet don't depends Spark.
I mean, the "most great Scala product" Spark is use Scala2.11,
So we can continue to use 2.11.
For example, Oracle release Jdk10 now, but most coder(program) use Jdk8,Jdk7...

[napgab]

You can continue to use 2.11, i am not saying to drop support to this version, but to support also 2.12.
if you want to compare with jvm versions, we are not talking about next generation jvm like java 10.
scala 2.10/11 stands at scala as jdk 6/7 stands at java.
today scala 2.12 is the target version in production environments, as java 8.

Just because scalnet does not depend on Spark, there is no reason to get stuck only on old versions like 2.10/11.

As far i understood, the problem here isn't Spark.
The only reason why is a difficult to upgrade is because the UI libraries are based on a older version of the play framework with scala 2.11. This should be the only dependency to scala 2.11.

[maxpumperla]

sure, I think we could add 2.12 to https://github.com/deeplearning4j/deeplearning4j/blob/master/change-scala-versions.sh and build scalnet for 2.12 as well here https://github.com/deeplearning4j/deeplearning4j/blob/master/scalnet/buildmultiplescalaversions.sh, but still leave 2.11 as default.

[kamilkloch]

Support for Scala 2.12 would be great news!

[kamilkloch]

Any chances for the 2.12 release? Spark now supports 2.12, meanwhile Scala 2.13 is around the corner...

[weihsiu]

please support scala 2.12/2.13. this has been a blocker for my organization to adapt scalnet and i really want them to try this great library...

[AlexDBlack]

Looks like Spark how has Scala 2.12 support (as of 2.4.0) - so this may be worth revisiting.
https://search.maven.org/artifact/org.apache.spark/spark-core_2.12/2.4.0/jar

However, the UI is still a problem here for us - we'd need to upgrade Play (which means dropping Scala 2.10 support for the UI) or try to work around supporting multiple versions of Play (Play does have some API changes in future versions, so it's not as simple as just upgrading the Play version).

[kamilkloch]

@AlexDBlack are there any monthly download statistics for Scala 2.10? Scala 2.10 represents a huge maintenance burden.

[saudet]

@chrisvnicholson should have some stats for that from Maven Central...

[AlexDBlack]

Usage stats aside, we'll likely continue to support Scala 2.10 as long as we have customers with Spark clusters running it. For us, Scala 2.10 isn't a major maintenance issue as we have very little in the way of Scala code (other than ND4S obviously) - it's just Scala dependencies like Spark and Play for us.

[napgab]

UI dependencies aside, i think that starting to provide a first release with support to scala 2.12 is a great first step.