Do not print diagnostic in the driver directly.

src/Generator/Driver.cs

@@ -68,7 +68,11 @@ namespace Cxxi
             }
 
             foreach (var diag in result.Diagnostics)
-                Console.WriteLine("    {0}", diag.Message);
+            {
+                Console.WriteLine(string.Format("{0}({1},{2}): error: {3}",
+                    diag.FileName, diag.LineNumber, diag.ColumnNumber,
+                    diag.Message));
+            }
         }
 
         public bool ParseCode()

src/Generator/Parser.cs

@@ -28,12 +28,7 @@ namespace Cxxi
                     {
                         if (diag.Level == ParserDiagnosticLevel.Error ||
                             diag.Level == ParserDiagnosticLevel.Fatal)
-                        {
-                            Console.WriteLine(string.Format("{0}({1},{2}): error: {3}",
-                                diag.FileName, diag.LineNumber, diag.ColumnNumber,
-                                diag.Message));
                             hasErrors = true;
-                        }
                     }
                 }
             }