sort classes in dependency order, or load lazily if needed, fixes #78

test/codegen/sunflower.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library sunflower;
 
 import 'dart:math';
 import 'dom.dart';
 
 const String ORANGE = "orange";
 const int SEED_RADIUS = 2;
 const int SCALE_FACTOR = 4;
 const num TAU = PI * 2;
 const int MAX_D = 300;
 const num centerX = MAX_D / 2;
 const num centerY = centerX;
 
 Element querySelector(String selector) => document.querySelector(selector);
 
 final InputElement slider = querySelector("#slider");
 final Element notes = querySelector("#notes");
 final num PHI = (sqrt(5) + 1) / 2;
 int seeds = 0;
 final CanvasRenderingContext2D context =
     (querySelector("#canvas") as CanvasElement).getContext('2d');
 
-// TODO(jmesserly): modified this example to use classes and mixins.
-class Circle {
-  final num x, y, radius;
+void main() {
+  slider.addEventListener('change', (e) => draw());
+  draw();
+}
 
-  Circle(this.x, this.y, this.radius);
+/// Draw the complete figure for the current number of seeds.
+void draw() {
+  seeds = int.parse(slider.value);
+  context.clearRect(0, 0, MAX_D, MAX_D);
+  for (var i = 0; i < seeds; i++) {
+    final num theta = i * TAU / PHI;
+    final num r = sqrt(i) * SCALE_FACTOR;
+    final num x = centerX + r * cos(theta);
+    final num y = centerY - r * sin(theta);
+    new SunflowerSeed(x, y, SEED_RADIUS).draw();
+  }
+  notes.textContent = "$seeds seeds";
+}
+
+// This example was modified to use classes and mixins.
+class SunflowerSeed extends Circle with CirclePainter {
+  SunflowerSeed(num x, num y, num radius, [String color])
+  : super(x, y, radius) {
+    if (color != null) this.color = color;
+  }
 }
 
 abstract class CirclePainter implements Circle {
   // This demonstrates a field in a mixin.
   String color = ORANGE;
 
   /// Draw a small circle representing a seed centered at (x,y).
   void draw() {
     context
       ..beginPath()
       ..lineWidth = 2
       ..fillStyle = color
       ..strokeStyle = color
       ..arc(x, y, radius, 0, TAU, false)
       ..fill()
       ..closePath()
       ..stroke();
   }
 }
 
-class SunflowerSeed extends Circle with CirclePainter {
-  SunflowerSeed(num x, num y, num radius, [String color])
-      : super(x, y, radius) {
-    if (color != null) this.color = color;
-  }
+class Circle {
+  final num x, y, radius;
+
+  Circle(this.x, this.y, this.radius);
 }
-
-void main() {
-  slider.addEventListener('change', (e) => draw());
-  draw();
-}
-
-/// Draw the complete figure for the current number of seeds.
-void draw() {
-  seeds = int.parse(slider.value);
-  context.clearRect(0, 0, MAX_D, MAX_D);
-  for (var i = 0; i < seeds; i++) {
-    final num theta = i * TAU / PHI;
-    final num r = sqrt(i) * SCALE_FACTOR;
-    final num x = centerX + r * cos(theta);
-    final num y = centerY - r * sin(theta);
-    new SunflowerSeed(x, y, SEED_RADIUS).draw();
-  }
-  notes.textContent = "$seeds seeds";
-}