Scala 2.10.4-RC3 is now available!

We are very happy to announce the third release candidate of Scala 2.10.4! If no serious blocking issues are found this will become the final 2.10.4 version.

The release is available for download from scala-lang.org or from Maven Central.

The Scala team and contributors fixed 31 issues since 2.10.3!

In total, 39 RC1 pull requests, 12 RC2 pull requests and 3 RC3 pull requests were merged on GitHub.

Known Issues

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

Scala IDE for Eclipse

The Scala IDE with this release 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 2.10.4 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

  • A class may now extend AnyVal to make it behave like a struct type (restrictions apply).
  • http://docs.scala-lang.org/overviews/core/value-classes.html

• Implicit Classes

  • The implicit modifier now also applies to class definitions to reduce the boilerplate of implicit wrappers.
  • http://docs.scala-lang.org/sips/pending/implicit-classes.html

• String Interpolation

  • val what = "awesome"; println(s"string interpolation is ${what.toUpperCase}!")
  • http://docs.scala-lang.org/overviews/core/string-interpolation.html

• Futures and Promises

  • Asynchronously get some JSON: for (req <- WS.url(restApiUrl).get()) yield (req.json \ "users").as[List[User]] (uses play!)
  • http://docs.scala-lang.org/overviews/core/futures.html

• Dynamic and applyDynamic

  • x.foo becomes x.applyDynamic("foo") if x's type does not define a foo, but is a subtype of Dynamic
  • http://docs.scala-lang.org/sips/pending/type-dynamic.html

• 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

  • Get on top of the advanced Scala features used in your codebase by explicitly importing them.
  • http://docs.scala-lang.org/sips/pending/modularizing-language-features.html

• Parallel Collections are now configurable with custom thread pools

  • http://docs.scala-lang.org/overviews/parallel-collections/overview.html

• Akka Actors now part of the distribution

  • scala.actors have been deprecated and the akka implementation is now included in the distribution.
  • See the actors migration project for more information.

• 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

• Scala Reflection

  • http://docs.scala-lang.org/overviews/reflection/overview.html

• Macros

  • http://docs.scala-lang.org/overviews/macros/overview.html

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 http://scalamacros.org/news/2012/11/05/status-update.html.

A big thank you to all the contributors!

# | Author ---: | --- 26 | Jason Zaugg 15 | Adriaan Moors 5 | Eugene Burmako 3 | A. P. Marki 3 | Simon Schaefer 3 | Mirco Dotta 3 | Luc Bourlier 2 | Paul Phillips 2 | François Garillot 1 | Mark Harrah 1 | Vlad Ureche 1 | James Ward 1 | Heather Miller 1 | Roberto Tyley

Commits and the issues they fixed since v2.10.3

Issue(s) | Commit | Message --- | --- | --- SI-7902 | 5f4011e | [backport] SI-7902 Fix spurious kind error due to an unitialized symbol SI-8205 | 8ee165c | SI-8205 [nomaster] backport test pos.lineContent SI-8126, SI-6566 | 806b6e4 | Backports library changes related to SI-6566 from a419799 SI-8146, SI-8146, SI-8146, SI-8146 | ff13742 | [nomaster] SI-8146 Fix non-deterministic <:< for deeply nested types SI-6443, SI-8143 | 1baf11a | SI-8143 Fix bug with super-accessors / dependent types SI-8152 | 9df2dcc | [nomaster] SI-8152 Backport variance validator performance fix SI-8111 | c91d373 | SI-8111 Expand the comment with a more detailed TODO SI-8111 | 2c770ae | SI-8111 Repair symbol owners after abandoned named-/default-args SI-7120, SI-8114, SI-7120 | 5876e8c | [nomaster] SI-8114 Binary compat. workaround for erasure bug SI-7120 SI-7636, SI-6563 | 255c51b | SI-6563 Test case for already-fixed crasher SI-8104, SI-8104 | c0cb1d8 | [nomaster] codifies the state of the art wrt SI-8104 SI-8085 | 7e85b59 | SI-8085 Fix BrowserTraverser for package objects SI-8085 | a12dd9c | Test demonstrating SI-8085 SI-6426 | 47562e7 | Revert "SI-6426, importable _." SI-8062 | f0d913b | SI-8062 Fix inliner cycle with recursion, separate compilation SI-7912 | 006e2f2 | SI-7912 Be defensive calling toString in MatchError#getMessage SI-8060 | bb427a3 | SI-8060 Avoid infinite loop with higher kinded type alias SI-7995 | 5ed834e | SI-7995 completion imported vars and vals SI-8019 | c955cf4 | SI-8019 Make Publisher check PartialFunction is defined for Event SI-8029 | fdcc262 | SI-8029 Avoid multi-run cyclic error with companions, package object SI-7439 | 8d74fa0 | [backport] SI-7439 Avoid NPE in isMonomorphicType with stub symbols. SI-8010 | 9036f77 | SI-8010 Fix regression in erasure double definition checks SI-7982 | 7d41094 | SI-7982 Changed contract of askLoadedType to unload units by default SI-6913 | 7063439 | SI-6913 Fixing semantics of Future fallbackTo to be according to docs SI-7458 | 02308c9 | SI-7458 Pres. compiler must not observe trees in silent mode SI-7548 | 652b3b4 | SI-7548 Test to demonstrate residual exploratory typing bug SI-7548 | b7509c9 | SI-7548 askTypeAt returns the same type whether the source was fully or targeted SI-8005 | 3629b64 | SI-8005 Fixes NoPositon error for updateDynamic calls SI-8004 | 696545d | SI-8004 Resolve NoPosition error for applyDynamicNamed method call SI-7463, SI-8003 | b915f44 | SI-7463,SI-8003 Correct wrong position for {select,apply}Dynamic calls SI-7280 | 053a274 | [nomaster] SI-7280 Scope completion not returning members provided by imports SI-7915 | 04df2e4 | SI-7915 Corrected range positions created during default args expansion SI-7776 | d15ed08 | [backport] SI-7776 post-erasure signature clashes are now macro-aware SI-6546 | 075f6f2 | SI-6546 InnerClasses attribute refers to absent class SI-7638, SI-4012 | e09a8a2 | SI-4012 Mixin and specialization work well SI-7519 | 50c8b39e | SI-7519: Additional test case covering sbt/sbt#914 SI-7519 | ce74bb0 | [nomaster] SI-7519 Less brutal attribute resetting in adapt fallback SI-4936, SI-6026 | e350bd2 | [nomaster] SI-6026 backport getResource bug fix SI-6026 | 2bfe0e7 | SI-6026 REPL checks for javap before tools.jar SI-7295 | 25bcba5 | SI-7295 Fix windows batch file with args containing parentheses SI-7020 | 7b56021 | Disable tests for SI-7020 SI-7783 | 2ccbfa5 | SI-7783 Don't issue deprecation warnings for inferred TypeTrees SI-7815 | 733b322 | SI-7815 Dealias before deeming method type as dependent

Complete commit list!

sha | Title ---: | --- 5f4011e | [backport] SI-7902 Fix spurious kind error due to an unitialized symbol 8ee165c | SI-8205 [nomaster] backport test pos.lineContent d167f14 | [nomaster] corrects an error in reify’s documentation 806b6e4 | Backports library changes related to SI-6566 from a419799 ff13742 | [nomaster] SI-8146 Fix non-deterministic <:< for deeply nested types cbb88ac | [nomaster] Update MiMa and use new wildcard filter 1baf11a | SI-8143 Fix bug with super-accessors / dependent types 9df2dcc | [nomaster] SI-8152 Backport variance validator performance fix c91d373 | SI-8111 Expand the comment with a more detailed TODO 2c770ae | SI-8111 Repair symbol owners after abandoned named-/default-args 5876e8c | [nomaster] SI-8114 Binary compat. workaround for erasure bug SI-7120 bd4adf5 | More clear implicitNotFound error for ExecutionContext 255c51b | SI-6563 Test case for already-fixed crasher c0cb1d8 | [nomaster] codifies the state of the art wrt SI-8104 7e85b59 | SI-8085 Fix BrowserTraverser for package objects a12dd9c | Test demonstrating SI-8085 3fa2c97 | Report error on code size overflow, log method name. 2aa9da5 | Partially revert f8d8f7d08d. 47562e7 | Revert "SI-6426, importable _." f0d913b | SI-8062 Fix inliner cycle with recursion, separate compilation 9cdbe28 | Fixup #3248 missed a spot in pack.xml 006e2f2 | SI-7912 Be defensive calling toString in MatchError#getMessage bb427a3 | SI-8060 Avoid infinite loop with higher kinded type alias 27a3860 | Update README, include doc/licenses in distro 139ba9d | Add attribution for Typesafe. e555106 | Remove docs/examples; they reside at scala/scala-dist dc6dd58 | Remove unused android test and corresponding license. f8d8f7d | Do not distribute partest and its dependencies. 5ed834e | SI-7995 completion imported vars and vals c955cf4 | SI-8019 Make Publisher check PartialFunction is defined for Event fdcc262 | SI-8029 Avoid multi-run cyclic error with companions, package object 8d74fa0 | [backport] SI-7439 Avoid NPE in isMonomorphicType with stub symbols. 9036f77 | SI-8010 Fix regression in erasure double definition checks 3faa2ee | [nomaster] better error messages for various macro definition errors 7d41094 | SI-7982 Changed contract of askLoadedType to unload units by default 7063439 | SI-6913 Fixing semantics of Future fallbackTo to be according to docs 02308c9 | SI-7458 Pres. compiler must not observe trees in silent mode 652b3b4 | SI-7548 Test to demonstrate residual exploratory typing bug b7509c9 | SI-7548 askTypeAt returns the same type whether the source was fully or targeted 0c963c9 | [nomaster] teaches toolbox about -Yrangepos 3629b64 | SI-8005 Fixes NoPositon error for updateDynamic calls 696545d | SI-8004 Resolve NoPosition error for applyDynamicNamed method call b915f44 | SI-7463,SI-8003 Correct wrong position for {select,apply}Dynamic calls 053a274 | [nomaster] SI-7280 Scope completion not returning members provided by imports eb9f0f7 | [nomaster] Adds test cases for scope completion 3a8796d | [nomaster] Test infrastructure for scope completion 04df2e4 | SI-7915 Corrected range positions created during default args expansion ec89b59 | Upgrade pax-url-aether to 1.6.0. 1d29c0a | [backport] Add buildcharacter.properties to .gitignore. 31ead67 | IDE needs swing/actors/continuations 852a947 | Allow retrieving STARR from non-standard repo for PR validation 40af1e0 | Allow publishing only core (pr validation) ba0718f | Render relevant properties to buildcharacter.properties d15ed08 | [backport] SI-7776 post-erasure signature clashes are now macro-aware 6045a05 | Fix completion after application with implicit arguments 075f6f2 | SI-6546 InnerClasses attribute refers to absent class e09a8a2 | SI-4012 Mixin and specialization work well 50c8b39e | SI-7519: Additional test case covering sbt/sbt#914 ce74bb0 | [nomaster] SI-7519 Less brutal attribute resetting in adapt fallback e350bd2 | [nomaster] SI-6026 backport getResource bug fix 2bfe0e7 | SI-6026 REPL checks for javap before tools.jar 25bcba5 | SI-7295 Fix windows batch file with args containing parentheses 7b56021 | Disable tests for SI-7020 8986ee4 | Disable flaky presentation compiler test. 2ccbfa5 | SI-7783 Don't issue deprecation warnings for inferred TypeTrees ee9138e | Bump version to 2.10.4 for nightlies 733b322 | SI-7815 Dealias before deeming method type as dependent