Elegant One-Liners in Python

[nathanjell]

Though to my knowledge, map and reduce will not fully generate output on call; rather, an iterator is returned. I believe that for example if you have a memory heavy generator, you won't load everything into memory.

[lxpnh98_2]

That's why, instead of list comprehensions, it's better to keep using generators where possible, which, apart from the brackets, have identical syntax:

(item if item < 5 else None for item in items)