Scala 2.10.3-RC3 is now available!

Tuesday 24 September 2013


We are very happy to announce the RC3 release of Scala 2.10.3! If no serious blocking issues are found this will become the final 2.10.3 version.

The release is available for download from or from Maven Central.

The Scala team and contributors fixed 50 issues since 2.10.2!

In total, 63 RC1 pull requests, 19 RC2 pull requests and 2 RC3 pull requests were opened on GitHub of which 72 were merged after having been tested and reviewed.

Known Issues

Before reporting a bug, please have a look at these known issues.

Scala IDE for Eclipse

The Scala IDE with Scala 2.10.3-RC3 built right in is available through the following update-site:

  • for Eclipse 4.2/4.3 (Juno/Kepler)

Have a look at the getting started guide for more info.

New features in the 2.10 series

Since 2.10.3 is strictly a bug-fix release, here’s an overview of the most prominent new features and improvements as introduced in 2.10.0:

  • Value Classes

  • Implicit Classes

  • String Interpolation

  • Futures and Promises

  • Dynamic and applyDynamic

  • Dependent method types:

    • def identity(x: AnyRef): x.type = x // the return type says we return exactly what we got
  • New ByteCode emitter based on ASM

    • Can target JDK 1.5, 1.6 and 1.7

    • Emits 1.6 bytecode by default

    • Old 1.5 backend is deprecated

  • A new Pattern Matcher

    • rewritten from scratch to generate more robust code (no more exponential blow-up!)

    • code generation and analyses are now independent (the latter can be turned off with -Xno-patmat-analysis)

  • Scaladoc Improvements

    • Implicits (-implicits flag)

    • Diagrams (-diagrams flag, requires graphviz)

    • Groups (-groups)

  • Modularized Language features

  • Parallel Collections are now configurable with custom thread pools

  • Akka Actors now part of the distribution

    • scala.actors have been deprecated and the akka implementation is now included in the distribution.
  • Performance Improvements

    • Faster inliner

    • Range#sum is now O(1)

    • Update of ForkJoin library

    • Fixes in immutable TreeSet/TreeMap

    • Improvements to PartialFunctions

  • Addition of ??? and NotImplementedError
  • Addition of IsTraversableOnce + IsTraversableLike type classes for extension methods
  • Deprecations and cleanup

    • Floating point and octal literal syntax deprecation

    • Removed scala.dbc

Experimental features

The API is subject to (possibly major) changes in the 2.11.x series, but don’t let that stop you from experimenting with them! A lot of developers have already come up with very cool applications for them. Some examples can be seen at

A big thank you to all the contributors!

# Author
1 Iulian Dragos
1 Jason Zaugg

Commits and the issues they fixed since v2.10.3-RC2

Issue(s) Commit Message
SI-7862 8e11dcb [nomaster] SI-7862: MANIFEST.MF file for Scala sources
SI-7861 7f4b44b SI-7861 Don't execute internal callbacks on the user Executor

Complete commit list!

sha Title
8e11dcb [nomaster] SI-7862: MANIFEST.MF file for Scala sources
7f4b44b SI-7861 Don't execute internal callbacks on the user Executor