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Dart Team Updates for March 2013


The Dart project continues to move forward rapidly, and Anders Sandholm fills us in on what members of the Dart team have been doing recently:


Dart Team Updates, Mar 6 - 19

Dart language specification:
  • Make mixins more useful (apply to arbitrary superclasses).
  • More consistent treatment of malformed types.
  • Examining mechanisms to suppress warnings and checked mode when needed.
  • Liberalizing function subtyping.
  • Develop synchronous mirror API for introspection.

Dart libraries:
  • Core:
    • Added List.asMap
    • remove deprecated Arrays, Date and StringBuffer.add/addAll/addCharCodes.
    • num.round, ceil, floor and truncate now return ints.
    • rename xMatching to xWhere.
    • Added Stream.periodic and rename Timer.repeating to Timer.periodic.
    • Made argument to StringSink.writeln optional.
  • dart:io:
    • Started adding support for detecting and working with symbolic links.
    • Added support for gzip encoding in the http server.
    • Lots of bugfixing after the introduction of dart:io v2. It is looking stable again.
  • dart:html:
    • Much more cleanup - e.g., converting maps to name parameters.
    • Canvas DrawImage improvements

dart2js Compiler:

  • Landed initial support for deferred loading of libraries.
  • Lots of improvements to the way we deal with generics.
  • First round of code size and performance improvements based on global type inferencing. We’re seeing some pretty good results and our scores on DeltaBlue and Richards have improved by ~27% and 8% respectively.
  • Started working on dart:typeddata support in dart2js.

Dartium:
  • Work in progress on using dart:typeddata for typed arrays in dart:html. This will dramatically speed up WebGL performance in Dartium.
  • Various improvements in debugger support
  • Bug fixes

Dart Editor:

  • New analyzer available via experimental preference. (work in progress, all features not enabled yet).
  • Package root preferences removed in favor of --package-root cmd line option
  • Reduced heap usage by ~25%.
  • Fixed a memory leak which could eventually consume 10% of the heap.
  • Fixed a notable Editor performance issue related to Pub and symlinks

Pub (rnystrom):
  • More work on the new tech scheduling framework: scheduled processes and servers
  • Development dependencies
  • Fixed more bugs

Dart Dev Rel (sethladd)


As always, view the changelog for the full list of changes, and to get started with the Editor, see our tutorial.

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