making more normal dart packages and libraries

Author: traceypowersg

Chapter_03/main.dart

@@ -1,6 +1,9 @@
+library recipe_book;
+
 import 'package:angular/angular.dart';
 import 'package:di/di.dart';
-import 'rating_component.dart';
+
+part 'rating_component.dart';
 
 @NgDirective(
     selector: '[recipe-book]',

Chapter_03/rating_component.dart

@@ -1,4 +1,4 @@
-import 'package:angular/angular.dart';
+part of recipe_book;
 
 /* Use the NgComponent annotation to indicate that this class is an
  * Angular Component.

Chapter_04/main.dart

@@ -1,8 +1,12 @@
+library recipe_book;
+
 import 'package:angular/angular.dart';
+import 'dart:convert';
 import 'package:perf_api/perf_api.dart';
 import 'package:di/di.dart';
-import 'rating_component.dart';
-import 'recipe.dart';
+
+part 'rating_component.dart';
+part 'recipe.dart';
 
 
 @NgFilter(name: 'categoryfilter')

Chapter_04/rating_component.dart

@@ -1,4 +1,4 @@
-import 'package:angular/angular.dart';
+part of recipe_book;
 
 /* Use the NgComponent annotation to indicate that this class is an
  * Angular Component.

Chapter_04/recipe.dart

@@ -1,6 +1,4 @@
-library recipe;
-
-import 'dart:convert' show JSON;
+part of recipe_book;
 
 class Recipe {
   String name;