Concatenation of array and range

[user1234]

On Sunday, 19 January 2025 at 18:57:51 UTC, Samuel Redding wrote:
> Hello there,
>
> is it possible to concat an array and a range? In Python one 
> would have
> """
> list1 = [1, 2, 3]
> list1 += array.array('L', range(a, b))
> """
>
> The equivalent in D should be something like
> """
> ulong[] list1 = [1, 2, 3];
> list1 ~= iota(a, b);
> """
>
> I haven't found a way to do this. The only way to do it seems 
> to extend "list1" and then iterate over the range and insert 
> the elements.

iota is a lazy range. As shown in the other answer you can yield 
the lazy thing using `.array`. But assuming it's ok to create a 
distinctive iterator you can also chain the two things:

```d
auto list2 = std.range.chain(list1,iota(a,b));
```

with list2 being fully lazy.