On Mon, Nov 27, 2017 at 03:31:38PM +0300, Kirill Balunov wrote:
As I can see at the moment, these cases should behave differently:
x, y = [1,2,3,4] # must raise ValueError x, y = iter([1,2,3,4]) # should work
I *completely disagree* that they should behave differently. That would be a radical change to the current equivalency between iterators and other iterables. Of course iterators support next() (and a few other things), while iterables (sequences and others) support slicing, __getitem__, and so forth. But when it comes to iteration, they behave exactly the same in all ways that I can think of: for x in iterable: ... list(iterable) iter(iterable) func(*iterable) and most importantly for this discussion, iterable unpacking: a, b, c = *iterable They all work the same, regardless of whether `iterable` is an iterator, a generator, a list, a tuple, a range object, a custom lazy sequence. Sure, there are a few differences: iterators generally cannot be restarted or rewound, while lazy sequences might be, and eager sequences like lists can be. You can't peek into an arbitrary iterator without consuming the value. But as far as iteration itself goes, they are all the same. -- Steve