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src/tests/site/code/syntax.dart

+import 'dart:math';                   // Import a library.
+
+abstract class Shape {
+  num get area;
+  num rotation = 0;
+  num outlineWidth = 1;
+  String color = 'black';
+}
+
+class Ellipse extends Shape {              // Declare a class.
+  num majorAxis = 0;                       // An instance variable (property).
+  num minorAxis = 0;
+  static const num C = PI/4;              // A constant.
+  num get area => C*majorAxis*minorAxis;   // A property implemented with a getter.
+
+  Ellipse(this.majorAxis, this.minorAxis); // Compact constructor syntax.
+  Ellipse.circle(diameter) {               // A named constructor.
+    minorAxis = majorAxis = diameter;
+  }
+  
+  // Override Object's toString() method.
+  String toString() =>
+      'Ellipse: ${majorAxis}x${minorAxis} ($area); rotation: $rotation; $color';
+}
+
+// Functions and variables can be inside or outside of classes.
+var shapes = new List();              // A global variable.
+addShape(shape) => shapes.add(shape); // Function shorthand syntax.
+
+// Every app has a main() function, where execution starts.
+main() {  
+  // The cascade operator (..) saves you from repetitive typing.
+  addShape(new Ellipse(10, 20)..rotation = 45*PI/180
+                              ..color = 'rgb(0,129,198)'
+                              ..outlineWidth = 0);
+  
+  // Convert expressions to strings using ${...}.
+  print('Area of the first shape: ${shapes[0].area}');
+  print(shapes[0]);
+}