Added koans for structural types

src/test/scala/org/scalakoans/AboutStructuralTypes.scala

@@ -0,0 +1,33 @@
+package org.scalakoans
+
+import support.KoanSuite
+
+class AboutStructuralTypes extends KoanSuite {
+
+  koan ("stuctural types") {
+    def sayHello(person: {def name: String}) = "Hello, " + person.name
+
+    case class Person(name: String)
+
+    val p = new Person("Lou")
+
+    sayHello(p) should be(__)
+
+    case class Person2
+    val p2 = new Person2
+    meditate
+    //sayHello(p2) should be(__)
+  }
+
+  koan ("defined structural type") {
+    type HasName = {def name: String}
+
+    def sayHello(person: HasName) = "Hello, " + person.name
+
+    case class Person(name: String)
+
+    val p = new Person("Lou")
+    sayHello(p) should be(__)
+  }
+
+}

src/test/scala/org/scalakoans/Koans.scala

@@ -12,6 +12,7 @@ class Koans extends Suite {
     new AboutClasses,
     new AboutObjects,
     new AboutPackages,
-    new AboutAbstractClasses
+    new AboutAbstractClasses,
+    new AboutStructuralTypes
   )
 }