On Fri, May 25, 2012 at 05:53:52PM +0100, Malcolm Wallace wrote:
Unless you show us the code, any answers will be guesses in the dark. Does your program use unsafePerformIO unsafely perhaps? Or a version of a library that happens to have a known bug?
No unsafePerformIO's or IOrefs or the like. The code itself is straight-forward (I think). It uses no external libraries -- just Data and System as bundled. One of the problems is that I don't know where in the code the problem may be arising -- the code is about 1200 lines, so it's not really practical to post it! (I'm starting to think that this issue may not be related to Haskell, as the problem arises so inconsistently -- sometimes the code runs, sometimes it bombs out early. I haven't rebooted the computer in a month or so, maybe it's time.) I guess what I'm asking is: what strategies should I be employing for debugging the problem? If the problem is with an array, for example, "error in array index" doesn't give me much to go on if I don't know which array may be the problem. Should I be trying to reproduce the problem in ghci's debugger, for example? Will that give me more context? --Mark