Wednesday, May 21, 2014

Dart 1.4 Brings Deep Visibility to Run Applications



It’s much easier to improve something if you can measure it. With Dart SDK 1.4, we are announcing Observatory: a comprehensive set of tools for understanding, measuring, and improving your Dart code.

As the documentation explains:
Observatory allows you to peek inside a running Dart virtual machine (VM) on demand and provides live, immediate reporting of data. You can use it to browse most aspects of an application.

Dart Observatory Screen Shot
The Observatory provides information on garbage collection, the instance count for all in-memory objects by their type, line-by-line code coverage, and even evaluation of arbitrary expressions. It will continue to evolve and improve in future releases. Take a look at the documentation and let us know if you have issues or suggestions.

Dart 1.4 also includes a number of other fixes, additions and improvements, including:
  • The dartanalyzer command line tool is now 100% Dart and runs without Java. Using dartanalyzer directly or via other tools requires only the Dart VM. 
  • File I/O is much faster, especially when accessing large files. 
  • We’ve added experimental support – Linux-only at the moment – for sharing network sockets across isolates
For a the complete summary of changes, read the release notes.

You can download Dart 1.4 from the Download Dart page. If you are running the Dart Editor, you can update by checking "About Dart Editor". Check out the Dart support page for information on getting help, filing issues, contributing to the project.

Thursday, May 8, 2014

Dart support for Internet Explorer

Dart v1.5, scheduled for late June, will be the last Dart release to support Internet Explorer 9. Dart will continue to support the latest releases of Firefox, Chrome, and Safari, as well as the two most recent releases of Internet Explorer – currently IE10 & IE11.

The factors we considered:

  • Most measures show IE9 usage is less than half of IE10 and IE11 combined.
  • The same measures often show IE9 usage trailing IE8.
  • A number of Google properties, including Google Apps, have ended support for IE9.
  • The Polymer project limits support to IE10+.

While we regret the impact to developers who would like to continue to support IE9, we are excited about the improvements this change will allow. For example, releases after Dart v1.5 will be able to use typed arrays across all of our libraries. Typed arrays are a web API for efficient access to raw binary data. Expanded use will help simplify and optimize the Dart SDK and enable developers to build faster and better experiences.

Please post on our discussion group if you have questions about our browser support policy or about our plans for typed arrays.