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Just angular
Upgrading to v4 will require more than updating your version constraint. The package has changed names (back) to angular – dropping the 2. You'll need to update yourpubspec.yaml and the corresponding imports in your
code. In most instances, find-and-replace should do the trick. Going forward,
the package will be called package:angular. We'll just update the version
number.
Smaller code
The updated compiler in 4.0 allows type-based optimizations that not only improve runtime performance but generate better code because we are able to strongly type templates. A big result of the update is that many applications will see compiled JavaScript sizes drop. In one case, we saw a 40KB (~10%) size drop in minified JavaScript by simply upgrading to v4. Every application is different, but we expect most applications will experience some code size reduction.Separation of concerns
Until now, AngularDart was a single package that contained not only core functionality, but also routing, forms, and testing. We've separated these libraries into separate packages:The code is managed under one repository, but each package can be used, versioned, and released separately. A breaking change in package:angular_forms won't require a breaking release of package:angular, for example. Having clear boundaries between packages also simplifies interdependencies between libraries, allowing dart2js to generate more efficient JavaScript.
New features
Besides being renamed and refactored, AngularDart v4 includes a number of new features. A couple of examples:Functional directives. A lightweight and stateless way to apply one-time transformations.
@Directive(selector: '[autoId]')
void autoIdDirective(Element element,
IdGenerator generator) {
element.id = generator.next();
}