Comment A more useful angle... (Score 2, Interesting) 674
Horror stories (lost rockets, etc) are certainly attention-getters, but a more useful question might be what kinds of errors got made, regardless of how severe the outcome.
For example, I once helped a newbie employee with a program that was working fine in a simple test case, but was blowing up when it tried to crunch through a production file.
After digging a little, I noticed that she was using recursion in her "GetNextInterestingRecord" routine! The logic was:
1) Get a record
2) See if it's the kind we want
3) If not, Call self
4) return record to main
I'm not sure why she chose to use recursion (too many classroom lectures on "cool" stuff and too little experience with getting useful stuff done?), but the program needed "interesting" records every so often to keep from overflowing the stack.
Clearly recursion should be confined to those problems where it's really needed, and not used just because you can find a way to state the problem using recursion. And even then, you need think about how big the stack will get, and what sorts of scenarios could cause it to get too big.
For example, I once helped a newbie employee with a program that was working fine in a simple test case, but was blowing up when it tried to crunch through a production file.
After digging a little, I noticed that she was using recursion in her "GetNextInterestingRecord" routine! The logic was:
1) Get a record
2) See if it's the kind we want
3) If not, Call self
4) return record to main
I'm not sure why she chose to use recursion (too many classroom lectures on "cool" stuff and too little experience with getting useful stuff done?), but the program needed "interesting" records every so often to keep from overflowing the stack.
Clearly recursion should be confined to those problems where it's really needed, and not used just because you can find a way to state the problem using recursion. And even then, you need think about how big the stack will get, and what sorts of scenarios could cause it to get too big.
