Any real world experience debugging a production functional program?

Question

I\'m interested in what tools and methods are used for diagnosing flaws in large scale functional programs. What tools are useful? My current understanding is that \'printf\'

Answer 1

A couple of years ago when I did this I had to use a combination of printf debugging and QuickCheck. These days I would also use the ghci built-in debugger.

The biggest headache was actually laziness causing space-time leaks. There still doesn't seem to be a good answer to these: just do lots of profiling and keep trying to figure it out.