[Insight-users] Suggestions for itk::ExceptionObject

[Niels Dekker]

I just wrote an exception class for our own C++ library at LKEB 
(www.lkeb.nl), that is very much inspired by itk::ExceptionObject: It is 
derived from std::exception, and it has a description, a source file name, a 
line number, and a function name.  I also copied your wonderful 
itkExceptionMacro(x) macro from itkMacro.h. Basically I very much appreciate 
the interface of itk::ExceptionObject, but I think its implementation could 
be improved. For instance, the copy constructor of itk::ExceptionObject 
might throw an std::bad_alloc.  Doing so might cause the program to 
terminate immediately.

I highly recommend you to check out the guidelines from "How should I design 
my exception classes?", by David Abrahams: 
http://www.boost.org/more/error_handling.html  Please take a look at 
guideline 2, 3, and 4:

  2. Use virtual inheritance
  3. Don't embed a std::string object
  4. Format the what() message on demand

Are there any plans to get itk::ExceptionObject in accordance to those 
guidelines?

FYI, For the implementation of our own Lkeb::Exception class, I'm using a 
reference counting mechanism, to make sure that its copy constructor never 
fails.

Kind regards,
--
Niels Dekker
http://www.xs4all.nl/~nd/dekkerware
Scientific programmer at LKEB, Leiden University Medical Center