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Introducing polymer.dart

Dart engineer John Messerly announces the launch of polymer.dart, a port of the Polymer stack. The Web UI package will be maintained for some time, but will eventually be replaced by polymer.dart.

Here is John's original post introducing polymer.dart:

Hello Dartisans,

Since we started Web UI, we've had a goal to bring the latest web standards like Web Components and Model-Driven Views to Dart developers. There have been some great developments since we started:

  • Web Components has progressed into a set of detailed specs (Custom Elements, Shadow DOM, HTML Templates, HTML Imports) with interest and implementation by multiple browser vendors.
  • Model-Driven Views has new APIs (Node.bind, TemplateElement.model) that allow custom elements to participate in the binding system, as well as the ability to plug in custom syntax, such as the fancy_syntax package.
  • dart:mirrors is now implemented in dart2js!
  • Last but not least: the development of the Polymer project. Polymer is a new type of JavaScript library for the web that builds on top of these emerging standards.

Today we continue our mission by publishing the beginnings of polymer.dart, our port of the Polymer stack. We’re pushing several packages to Pub: observe, mdv, shadow_dom, and the polymer.dart package.  The Dart team is collaborating with the Polymer team to ensure that polymer.dart elements and polyfills are fully compatible with Polymer.

This is only the beginning. Polymer and web components are evolving, and we’re going to keep bringing that to you. Some of the things we’ll be working on are:
  • declarative <polymer-element> and custom elements.
  • more new, up-to-date polyfill packages, like html_imports.
  • removing the mandatory compiler step for polymer.dart. Just edit, save & refresh!
  • bring the Polymer UI elements to Dart.
  • up to date documentation for all of this shiny new stuff.

It's still very early for polymer.dart, but we welcome you to try out the new packages. We’ll be maintaining the web_ui package for a considerable time, but will eventually be sunsetting it in favor of Polymer. Thanks in advance for your feedback as we continue the port and evolve the specs and implementations. We hope you’re as excited as we are about Polymer, and can't wait to see what you build!

Thanks!

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