Initial data commit

Task/Undefined-values/Wren/undefined-values.wren

@@ -0,0 +1,15 @@
+var f = Fn.new {
+    System.print("'f' called.") // note no return value
+}
+
+var res = f.call()
+System.print("The value returned by 'f' is %(res).")
+
+var m = {} // empty map
+System.print("m[1] is %(m[1]).")
+
+var u  // declared but not assigned a value
+System.print("u is %(u).")
+
+var v = null // explicitly assigned null
+if (!v) System.print("v is %(v).")