This question already has an answer here:
I often find it cleaner to write a generator than to return a list. For example, I prefer
def my_func_gen(foo): for i in foo: # Do some stuff that's too complicated for a list or generator comprehension yield whatever
def my_func_list(foo): result =  for i in foo: # Do some stuff that's too complicated for a list or generator comprehension result.append(whatever) return result
Further, this answer says, "You're encouraged to use iterators for everything." So is
my_func_gen better, then? Maybe not. I'd like for the caller not to even know whether it's getting a list or an iterator. But the caller has to think about it because, for example, the iterator won't be sliceable using Python's nice clean syntax; I'll have to use
So what should I do?
- Ignore the advice to "use iterators for everything"
- Get out of the habit of using slices and other behavior that's not available to all iterables
list(my_iterable)any time I might want to use features that lists support and generators do not
- Use lists sometimes and generators others. But when?
Related: here's some code that users a wrapper class to make any iterator sliceable. It doesn't work quite the way you might think, though: looking up
foo[:2] and then looking up
foo[:2] again gives different results.