2) Don't worry about memory leaks until they actually appear. If they do, use a profiling tool to find out what's going on. Most likely, one of the two things above happened in an interesting way.
At the risk of sounding stupid in Haskell mode, how would I be aware of this other than obvious messages or seg-faults about memory getting low ?
It is likely that, if you develop a medium to large sized application for a customer, memory leaks will appear at the customers site. It will often be very difficult to reproduce the situation and find the leak.
That scares me enough to not want to use Haskell for serious application development. With 26 years in the trade I have had too many times when a fault cannot be reproduced and despite an 'obvious fault in the source' being fixed and the problem never coming back, without being able to reproduce and thus confirm that you have eliminated the problem, you can't ever relax on a Saturday night! LOL I hate the word 'random' when clients describe problems too!
If you want to produce quality software, it is best to be sure what you are doing during the whole development process. There should be a set of guidelines, on how to prevent space leaks.
I guess "being sure..." comes with experience of the language, like any other. I can 'think' in quite a few languages with complete confidence, knowing that things will just work. I guess Haskell is a bigger elephant sandwich! There is something beautiful about its syntax and the fact that everything is (or can be) so precise and concise, sometimes a little too concise for me to read. It *makes* me want to be in that club just so I can have that level of understaning about my job. I learned BASIC and UCSD-PASCAL at age 11 and I have never stopped being fascinated about *what* computing is all about. Sometimes I think that a CPU *is* a perfectly enlightened consciousness always in the *now*. Time for my medication and music therapy.....
See also "On the reliability of programs", http://www.cs.utexas.edu/users/EWD/transcriptions/EWD03xx/EWD303.html
Will do, thanks. Sean