I was looking for a way to implement this more pythonically. And this looks great. But it made me think that if x and y are of different lengths, the last itera

I was looking for a way to implement this more pythonically. And this looks great. But it made me think that if x and y are of different lengths, the last iteration might consume an element out of the longer iterator. So I tried it with the builtin `zip(a,b)`, and indeed, if a is shorter, `zip(a,b)` consumes the same number of elements from both a and b. But if a is longer, then `zip(a,b)` consumes one extra element from a. I don't know if this behavior is well defined, that is whether I can rely on this, or the order of evaluation of the arguments of a function is up to the interpreter/compiler, and may change. masklinn wrote a comment in another thread about this that i didn't understand until I saw your implementation.