Director exceptions now derive from std::exception

Lib/d/director.swg

@@ -9,6 +9,7 @@
 #include <iostream>
 #endif
 #include <string>
+#include <exception>
 
 namespace Swig {
 
@@ -17,28 +18,25 @@ namespace Swig {
   };
 
   // Base class for director exceptions.
-  class DirectorException {
+  class DirectorException : public std::exception {
   protected:
     std::string swig_msg;
 
   public:
-    DirectorException(const char *msg) : swig_msg(msg) {
-    }
-
     DirectorException(const std::string &msg) : swig_msg(msg) {
     }
 
-    const std::string& what() const {
-      return swig_msg;
+    virtual ~DirectorException() throw() {
     }
 
-    virtual ~DirectorException() {
+    const char *what() const throw() {
+      return swig_msg.c_str();
     }
   };
 
   // Exception which is thrown when attempting to call a pure virtual method
-  // from D code thorugh the director layer.
-  class DirectorPureVirtualException : public Swig::DirectorException {
+  // from D code through the director layer.
+  class DirectorPureVirtualException : public DirectorException {
   public:
     DirectorPureVirtualException(const char *msg) : DirectorException(std::string("Attempted to invoke pure virtual method ") + msg) {
     }