Dart Team's Weekly Digest

Posted by Anders Sandholm

Quick update on what happened in Dart-land this week.

• While we’ve seen the first steps taken in local inspection in the debugger in Dartium, the VM is implementing debugger stepping. The VM is also adding support for object groups to enable proper GC in Dartium and we’ve seen the first few code reviews, commits and build breaks by the new compiler infrastructure. Finally, the VM team has been fixing overly aggressive type checks which should only be static type warnings.
• In the editor, we only generate JS when launching a Dart app in a non-Dartium browser, we introduced a switch to always use Frog for JS code generation and cleaned up the welcome page. Finally, a few omnibox search improvements were landed along with analysis performance improvements and general fixes.
• Wrapper-less HTML generator was checked in and we had lots of infrastructure work - getting rid of instability in buildbots, testing frog hosted in browser (with frogpad).
• In the dart:io library, performance of asynchronous directory and file operations improved using a native thread pool instead of isolates. The improvement is more than a factor of 80(!) on a loop that just creates and deletes files. Yay! Also, file APIs were extended with convenience methods for reading the whole contents of a file with one simple call (readAsBytes, readAsText, readAsLines).
  Example: new File(‘file.txt’).readAsText(‘UTF-8’);