What (if any) performance advantages are offered by using iterators. It seems like the 'Right Way' to solve many problems, but does it create faster/more memory-conscious code? I'm thinking specifically in Python, but don't restrict answers to just that.
There's actually a very good mail on the python mailing list about this: Iterators vs Lists. It's a bit dated (from 2003), but as far as I know, it's still valid.
Here's the summary:
For small datasets, iterator and list based approaches have similar performance. For larger datasets, iterators save both time and space.
What I would draw from it is this: iterators are to be preferred over loading data into a list if possible. But unless you have a big dataset, don't contort your code to make something that should fit in a list to work with an iterator.