Taking abstract generic programming into C++

Thursday, December 21st, 2006

Well, if you've been educated on university level in software engineering you'll probably remember something about abstract data types and meta programming. There are several trends that tries to move these "paradigms" into the practical programming world. For example I've just noticed that the ANSI/ISO C++ Standard is considering/examining to support generic programming (or ConceptC++ for laymen), the standard is dubbed C++0x. Some refer to this to taking C++ to the next level (see), uhh...

A good page to get some information about this is the website www.generic-programming.org. Read the small ConceptC++ tutorial and you may get the idea.

What eludes me at the current point in time what real world practical problems all this solves  I better read about more about it... I have a feeling that we will see more to it. For now, I believe that it should "solve" the following:

• provide better compiler error message when dealing with templates. We all know the current state of C++ compilers when they output errors related templates - they are messy! So this is a good thing.
• provide "abstractions" without performance penalties.  It seems that generic programming can do just that. Again a good thing.
• provide the means for library developers to abstract away data types - i.e. they do not need to care about the fundamental data representation but can focus on the algorithms provided by the library.

There are references to generic C++ libraries, other than the Standard C++ Library, which are based on generic programming. Most of them are geared towards mathematical communities - even thought most of the solved problems have real use in specific day-to-day areas. It's just hard to grasp!

More:

• The ConceptGCC Developer blog.
• A nice example of using generic programming - which may be more easy to understand than the more mathematical focused libraries - is the Adobe Generic Image Library, which nicely have extracted away how an image is represented and therefore enable you to focus on the (image) algorithms.