samples from presentation

examples/src/HelloNames.kt

@@ -1,7 +1,7 @@
 namespace HelloNames
 
 fun main(args : Array<String>) {
-    var names : String = ""
+    var names = ""
 
     for (i in args.indices) {
         names += args[i]

examples/src/HelloNamesFaster.kt

@@ -0,0 +1,22 @@
+namespace HelloNamesFaster
+
+fun main(args : Array<String>) {
+    var names = StringBuilder()
+
+    for (i in args.indices) {
+        names += args[i]
+        if (i + 1 < args.size)
+            names += ", "
+    }
+    // string templates
+    println("Hello, $names!")
+}
+
+fun println(message : String) {
+    // System.out is a nullable field
+    System.out?.println(message)
+}
+
+fun StringBuilder.plusAssign(s : String) {
+    this.append(s)
+}