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Scala 2.11.0 Release Notes

scala-lang.org

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Re: Scala 2.11.0 Release Notes

#31

Post by frowaway001 »

film42 wrote: post #29
gourlaysama wrote: post #24

Earlier quoted context omitted.

AbstractFunction, Function, Product and Tuple are all still limited to 22. Increasing the limit would create too much bytecode, and in the current design, lifting the limit is just impossible (without runtime code generation or custom classloader, etc.).

So why did they choose to allow case classes to have arbitrary arity? Not that I'm complaining, I just don't understand the underworking of scala that well.

They just don't emit all the boilerplate which would require unlimited-arity Tuples/Functions/... for larger case classes.

Re: Scala 2.11.0 Release Notes

#32

Post by acjohnson55 »

gourlaysama wrote: post #24
neverminder wrote: post #22

Earlier quoted context omitted.

As the matter of fact I'm not sure now. I was looking for a confirmation that tuple limit is removed in Scala 2.11, but couldn't find it whereas statements that case class 22 parameter limit is removed are all over the place.

AbstractFunction, Function, Product and Tuple are all still limited to 22. Increasing the limit would create too much bytecode, and in the current design, lifting the limit is just impossible (without runtime code generation or custom classloader, etc.).

film42: I think it was driven by Slick and the need to accommodate database tables with more than 22 columns

Re: Scala 2.11.0 Release Notes

#34

Post by neverminder »

acjohnson55 wrote: post #32
gourlaysama wrote: post #24

Earlier quoted context omitted.

AbstractFunction, Function, Product and Tuple are all still limited to 22. Increasing the limit would create too much bytecode, and in the current design, lifting the limit is just impossible (without runtime code generation or custom classloader, etc.).

film42: I think it was driven by Slick and the need to accommodate database tables with more than 22 columns

Indeed, because the fallback is HList and when I have tables up to 200 columns it's killing the CPU and crashing Scala IDE up to the point where you just can't work with it.

Re: Scala 2.11.0 Release Notes

#36

Post by eranation »

some_pythonista wrote: post #13

Relevant: "Functional Programming Principles in Scala" starts in 4 days on coursera, which was created by the author of scala. https://www.coursera.org/course/progfun

This is a great course, love it and recommend any developer taking it.

Having that said, if all you want is to "switch from imperative language X to Scala", (e.g. from Java) and you want to learn first how to do the "non functional" stuff in Scala, then keep in mind that this course is teaching functional programming first, Scala later. You can do (if you want) very imperative and object oriented style of coding in Scala but this course is not focusing on that part of the language (not because it's bad, but simply because the course is about functional programming)

With that said, go and enroll, it's one of the best coursera courses I took. Great videos, and very interesting programming assignments (many are adaptations from SICP I later learned) and great forum discussions.

Re: Scala 2.11.0 Release Notes

#37

Post by agumonkey »

some_pythonista wrote: post #13

Relevant: "Functional Programming Principles in Scala" starts in 4 days on coursera, which was created by the author of scala. https://www.coursera.org/course/progfun

A nice complementary one on coursera is proglang, taught by Dan Grossman (at least the first run was), uses racket/sml/ruby.

Very nice, with a focus on interpretation and comparison points between paradigms.

Re: Scala 2.11.0 Release Notes

#38

Post by soq_4 »

adriaanm wrote: post #7
frowaway001 wrote: post #5

Earlier quoted context omitted.

There have not been any huge library/language changes since 2.8.

To be fair, 2.10 introduced quite a few new features (my favorite being string interpolation). To name some more: implicit classes, value classes, language imports, reflection & macros,... 2.11 set the tone for the remainder of the 2.x cycle: smaller, faster, stabler. 2.12 will focus on Java 8 support and making it (even) easier to learn and use Scala. We're also working on making the compiler a better platform for o…

I really hope that you guys aren't planning to pull a Python 3 with the 3.x series. We're using Scala quite heavily in our production systems and the naysayers will have a great "I told you so" moment of we end up sitting on a ton of critical Scala code which no longer compiles in a future version.

Re: Scala 2.11.0 Release Notes

#39

Post by soq_4 »

film42 wrote: post #4

Probably the best change in my opinion was resolving the arity limit for case classes: https://issues.scala-lang.org/browse/SI-7296 I've bumped up against that limit pretty bad while trying to deserialize json. Shapeless did a lot to solve the problem, but I'm sure glad that limit has been removed.

Another really big change is the AnyRefMap class which provides a very fast mutable hashmap. There's also a specialized map for keys of type long.
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