1\. For your first question, it shouldn't introduce overhead as it's an inline
iterator. You can check the generated C code.
If we take a simple seq this is equivalent to the following
iterator foo_item[T](s: seq[T]): T =
for i in 0 ..< s.len:
yield s[i]
let a = @[1, 2, 3, 4]
for val in foo_item(a):
echo val
The reason why I use an intermediate zip is for Arraymancer. This is a proof of
concept before I generalize it to tensors.
On tensors, it would be wrapped in an OpenMP template that splits the work on
multiple cores like
[here](https://github.com/mratsim/Arraymancer/blob/e801b78169b59f1213a2e046997cfecf99ed4feb/src/tensor/higher_order_applymap.nim#L31-L43).
I also really need an iterator because the "next" item is not straightforward
if the tensor is not contiguous, see
[here](https://github.com/mratsim/Arraymancer/blob/e801b78169b59f1213a2e046997cfecf99ed4feb/src/tensor/private/p_accessors.nim#L144-L148).
2\. Thanks, fixed. Yes if they are not the same length it generates an error.
3\. Indeed that's a much better syntax, I have absolutely no idea how to
introduce it though.
Bonus, I added loopFusion:
import loopfusion
let a = @[1, 2, 3]
let b = @[11, 12, 13]
let c = @[10, 10, 10]
let d = @[5, 6, 7]
loopFusion(d,a,b,c):
let z = b + c
echo d + a * z
