commit | 1492a292e261bf23d64ef49b7890010f3df77d96 | [log] [tgz] |
---|---|---|
author | Timothy Blasi <kegluneq@users.noreply.github.com> | Tue Feb 03 15:46:04 2015 -0800 |
committer | Timothy Blasi <kegluneq@users.noreply.github.com> | Tue Feb 03 15:46:04 2015 -0800 |
tree | 513f23f9946f361aeed67bd8be213de0a275c25b | |
parent | 5ee257e571d3e4b79e1ef3f79a590a6309ef66ae [diff] |
Update docs with new transformer parameter names entryPoint > entry_point newEntryPoint > new_entry_point htmlEntryPoint > html_entry_point
This package provides a common interface for initialization annotations on top level methods, classes, and libraries. The interface looks like this:
abstract class Initializer<T> { dynamic initialize(T target); }
The initialize
method will be called once for each annotation. The type T
is determined by what was annotated. For libraries it will be the Symbol representing that library, for a class it will be the Type representing that class, and for a top level method it will be the Function object representing that method.
If a future is returned from the initialize method, it will wait until the future completes before running the next initializer.
Ther is one initializer which comes with this package, @initMethod
. Annotate any top level function with this and it will be invoked automatically. For example, the program below will print hello
:
import 'package:initialize/initialize.dart'; @initMethod printHello() => print('hello'); main() => run();
In order to run all the initializers, you need to import package:initialize/initialize.dart
and invoke the run
method. This should typically be the first thing to happen in your main. That method returns a Future, so you should put the remainder of your program inside the chained then call.
import 'package:initialize/initialize.dart'; main() { run().then((_) { print('hello world!'); }); }
During development a mirror based system is used to find and run the initializers, but for deployment there is a transformer which can replace that with a static list of initializers to be ran.
This will create a new entry point which bootstraps your existing app. If you supply an html_entry_point
then any script tags whose src is the same as entry_point
will be rewritten to the bootstrapped file new_entry_point
.
Below is an example pubspec with the transformer:
name: my_app dependencies: initialize: any transformers: - initialize: entry_point: web/index.dart new_entry_point: web/index.bootstrap.dart html_entry_point: web/index.html
Lets look at a slightly simplified version of the @initMethod
class:
class InitMethod implements Initializer<Function> { const InitMethod(); @override initialize(Function method) => method(); }
You would now be able to add @InitMethod()
in front of any function and it will be automatically invoked when the user calls run()
.
For classes which are stateless, you can usually just have a single const instance, and that is how the actual InitMethod implementation works. Simply add something like the following:
const initMethod = const InitMethod();
Now when people use the annotation, it just looks like @initMethod
without any parenthesis, and its a bit more efficient since there is a single instance. You can also make your class private to force users into using the static instance.