Scala 2.10.4 is now available!

We are very happy to announce the final release of Scala 2.10.4!

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

The Scala team and contributors fixed 33 issues since 2.10.3!

In total, 36 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): * Development version (Scala IDE 3.0.3-rc3 on Scala 2.10.4) * Stable version (will have 2.10.4 as soon as Scala IDE 3.0.3-vfinal is released)

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