Python bindings - exceptions

It is permissible for a reflected C++ function called from Python to throw an exception, as long as the exception inherits from IException. For example:

// C++ code
namespace ns
{
    struct Apollo13Failure : public IException
    {
        virtual void Write(std::ostream& os) const
        {
            os << "Houston, we have a problem";
        }
    };

    $function+ void FlyToMoon()
    {
        throw Apollo13Failure();
    }
}

In the code below Python calls the function FlyToMoon() which throws an exception of type Apollo13Failure. As required, this inherits from IException. In Python, this causes a RuntimeError exception to be thrown, with a string value equal to the string written by the virtual Write() method of the C++ IException.

# python code
try:
    ns.FlyToMoon()
except RuntimeError, e:
    print e

which produces the following output:

Houston, we have a problem