How about this:
Scala doesn't - quite - have the safety and conciseness of Haskell. But it's close.
Scala doesn't - quite - have the enterprise support and tooling infrastructure (monitoring/instrumentation, profiling, debugging, IDEs, library ecosystem) that Java does. But it's close.
Scala doesn't - quite - have the clarity of Python. But it's close.
Scala doesn't - quite - have the performance of C++. But it's close.
To summarize: Scala to me is just a better Java with too many trade offs.
If you're treating Scala as "just a better Java" then you're not writing inefficient code; you're writing code that could be better Scala code but is still better than the Java you would otherwise have written. Even if you never move beyond the "Java without semicolons" stage, hey, it saved you writing all those semicolons.
But Scala absolutely is a full language and not just a better Java; Java 8 barely scratches the surface of what you can do in Scala. I don't think I could bear to work in a language without higher-kinded types again.
Kafka has some very particular constraints that I don't think apply in general; remember they're making a framework rather than an application.
> they realized that almost all of the features are available
Interesting too. Looking at the stuff I'm currently doing, there is plenty of stuff which is just impossible in Java.
By the way, isn't "Scala has such a nice type system that it blows out OCaml from the water" already the case?
Scala was that at first. Arguably that's still Typesafe's primary interest.
> By the way, isn't "Scala has such a nice type system that it blows out OCaml from the water" already the case?
Yes and no. It's more featureful (higher-kinded types are really nice), but less elegant and type inference works less well (in part because scala has both inheritance and typeclasses).
I don't doubt your sincerity.
Try to pull yourself out and understand it as an investor:
$500 a day to pay for a scala engineer. Not a word about the bottom line.
Python? Ruby? Are they algorithmically fast? No, but they ship and sell.
> $500 a day to pay for a scala engineer. Not a word about the bottom line.
Maybe - I don't make that much and I have 5 years' Scala experience. (I have a relaxed environment and great culture though, so I'm not complaining). What I really don't get is Java companies where developers are chomping at the bit to use Scala and management says no - your devs are volunteering to become devs that companies would pay 2x for, the least you can do is let them.
The last major version and the next major version don't ship with any new feature at all, and removing some stuff, so it's a bit hard to see were you are coming from.
Python has PEP's. C and C++ have a ISO standards body. JDK has JEP. Adding a new library feature, let alone overhauling core types, is something scala added as if it was no big deal.
In python, when "new classes" were introduced, it was a big honking deal! You can bet it was heard about everywhere, in the documentation, etc. cpython interpreters like python 2.6 have support going back 5 years, and the changes between 2.x python versions are small compared scala.
There's a reason why enterprise languages move like a toad. We can't have legacy systems breaking. We want our legacy libraries to keep working. In 2015, I write python 2.6 code that works in python 3.5-dev, because they carefully planned releases and I write idiomatically.
Ask yourself if uninitiated generalist prorgammers can really grasp those hieroglyphic walls of text. It's encoding too much information too densely, and inside the density, there's so many clever tricks that block could doing.
It entices solipsistic programming. Long evenings and hard work goes into programming blocks of logic that aren't portable or readable as a future consolidation. This is where scala user's get protective. Their mental thought is legitimate, the output however means nothing to fellow coders.
With java, you could say we satisfy the longterm code quality. Even though I'm cynical of the JVM, I realize that my time and effort would hold out on the long term and my team would have code that would be a legacy into the future.
With scala, their is a sense of urgency coupled with a legitimate sense of eureka! But it all ends up looking like schizophrenic scribbling on a napkin to others.
Scala must limit the grammar in your programming language.
