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doc/quick_start_en.md

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+# Quick start
+
+## Main components DI
+
+
+### Binding
+
+Binding is a custom instance configurator that contains methods for configuring a dependency.
+
+There are two main methods for initializing a custom instance `toInstance ()` and `toProvide ()` and auxiliary `withName ()` and `singeltone ()`.
+
+`toInstance()` - takes a initialized instance
+
+`toProvide()` -  takes a `provider` function (instance constructor)
+
+`withName()` - takes a string to name the instance. By this name, it will be possible to extract instance from the DI container
+
+`singeltone()` -  sets a flag in the Binding that tells the DI container that there is only one dependency.
+
+Example:
+
+```dart
+ // initializing a text string instance through a method toInstance()
+ Binding<String>().toInstance("hello world");
+
+ // or
+
+ // initializing a text string instance
+ Binding<String>().toProvide(() => "hello world");
+
+ // initializing an instance of a string named
+ Binding<String>().withName("my_string").toInstance("hello world");
+ // or
+ Binding<String>().withName("my_string").toProvide(() => "hello world");
+
+ // instance initialization like singleton
+ Binding<String>().toInstance("hello world");
+ // or
+ Binding<String>().toProvide(() => "hello world").singeltone();
+
+```
+
+### Module
+
+Module is a container of user instances, and on the basis of which the user can create their modules. The user in his module must implement the `void builder (Scope currentScope)` method.
+
+
+Example:
+
+```dart
+class AppModule extends Module {
+  @override
+  void builder(Scope currentScope) {
+    bind<ApiClient>().toInstance(ApiClientMock());
+  }
+}
+```
+
+### Scope
+
+Scope is a container that stores the entire dependency tree (scope, modules, instances).
+Through the scope, you can access the custom `instance`, for this you need to call the `resolve<T>()` method and specify the type of the object, and you can also pass additional parameters.
+
+Example:
+
+```dart
+    // open main scope
+    final rootScope =  DartDi.openRootScope();
+
+    // initializing scope with a custom module
+    rootScope.installModules([AppModule()]);
+
+    // takes custom instance
+    final str = rootScope.resolve<String>();
+    // or
+    final str = rootScope.tryResolve<String>();
+
+    // close main scope
+    DartDi.closeRootScope();
+```
+
+## Example app
+
+
+```dart
+import 'dart:async';
+import 'package:meta/meta.dart';
+import 'package:dart_di/experimental/scope.dart';
+import 'package:dart_di/experimental/module.dart';
+
+class AppModule extends Module {
+  @override
+  void builder(Scope currentScope) {
+    bind<ApiClient>().withName("apiClientMock").toInstance(ApiClientMock());
+    bind<ApiClient>().withName("apiClientImpl").toInstance(ApiClientImpl());
+  }
+}
+
+class FeatureModule extends Module {
+  bool isMock;
+
+  FeatureModule({required this.isMock});
+
+  @override
+  void builder(Scope currentScope) {
+    bind<DataRepository>()
+        .withName("networkRepo")
+        .toProvide(
+          () => NetworkDataRepository(
+            currentScope.resolve<ApiClient>(
+              named: isMock ? "apiClientMock" : "apiClientImpl",
+            ),
+          ),
+        )
+        .singeltone();
+    bind<DataBloc>().toProvide(
+      () => DataBloc(
+        currentScope.resolve<DataRepository>(named: "networkRepo"),
+      ),
+    );
+  }
+}
+
+void main() async {
+  final scope = openRootScope().installModules([
+    AppModule(),
+  ]);
+
+  final subScope = scope
+      .openSubScope("featureScope")
+      .installModules([FeatureModule(isMock: true)]);
+
+  final dataBloc = subScope.resolve<DataBloc>();
+  dataBloc.data.listen((d) => print('Received data: $d'),
+      onError: (e) => print('Error: $e'), onDone: () => print('DONE'));
+
+  await dataBloc.fetchData();
+}
+
+class DataBloc {
+  final DataRepository _dataRepository;
+
+  Stream<String> get data => _dataController.stream;
+  StreamController<String> _dataController = new StreamController.broadcast();
+
+  DataBloc(this._dataRepository);
+
+  Future<void> fetchData() async {
+    try {
+      _dataController.sink.add(await _dataRepository.getData());
+    } catch (e) {
+      _dataController.sink.addError(e);
+    }
+  }
+
+  void dispose() {
+    _dataController.close();
+  }
+}
+
+abstract class DataRepository {
+  Future<String> getData();
+}
+
+class NetworkDataRepository implements DataRepository {
+  final ApiClient _apiClient;
+  final _token = 'token';
+
+  NetworkDataRepository(this._apiClient);
+
+  @override
+  Future<String> getData() async => await _apiClient.sendRequest(
+      url: 'www.google.com', token: _token, requestBody: {'type': 'data'});
+}
+
+abstract class ApiClient {
+  Future sendRequest({@required String url, String token, Map requestBody});
+}
+
+class ApiClientMock implements ApiClient {
+  @override
+  Future sendRequest(
+      {@required String? url, String? token, Map? requestBody}) async {
+    return 'Local Data';
+  }
+}
+
+class ApiClientImpl implements ApiClient {
+  @override
+  Future sendRequest(
+      {@required String? url, String? token, Map? requestBody}) async {
+    return 'Network data';
+  }
+}
+```