On 1/6/23 15:23, Arredondo wrote:

> then you get an exception (incorrect startup parameters).

Although that difference is a bug, iota does have a special floating point implementation to prevent the accumulation of floating point errors. I mention it as item 4 here:

  https://www.youtube.com/watch?v=gwUcngTmKhg&t=634s

Briefly, iota's regular popFront() is a trivial

  front += step

but it is

  ++n

for floating types so that front can be

  begin + (n * step)

for them.

The iota discussion starts at an earlier point in the video here:

  https://www.youtube.com/watch?v=gwUcngTmKhg&t=558s

Ali

On Saturday, 7 January 2023 at 00:52:20 UTC, Ali Çehreli wrote:
> Although that difference is a bug, iota does have a special floating point implementation to prevent the accumulation of floating point errors.

Thank you for this clarification Ali. I appreciate the fact that there is a specialized implementation for float types in an attempt to mitigate error accumulation.

After posting my previous message I became convinced that the behavior I was seeing was indeed a bug. The specialized fp implementation simply does not conform to the semantics specified in the documentation: "If begin < end && step < 0 or begin > end && step > 0 or begin == end, then an empty range is returned."

The culprit is this assert in the `in` block of the fp implementation:

```
assert((end - begin) / step >= 0, "iota: incorrect startup parameters");
```

This effectively prevents iota from ever returning an empty range. Git blame points to a commit from March 2015. It's unbelievable to me this hasn't been fixed in almost 8 years.

Would anyone volunteer to file a bug report? I attempted to do it myself but I would need to create an account in the Issue Tracking System, and apparently it doesn't accept gmail addresses anymore? (facepalm).

Arredondo.

On 1/6/23 17:50, Arredondo wrote:

> Would anyone volunteer to file a bug report?

Me! Me! :)

  https://issues.dlang.org/show_bug.cgi?id=23604

Ali

On Saturday, 7 January 2023 at 02:31:14 UTC, Ali Çehreli wrote:
> On 1/6/23 17:50, Arredondo wrote:
>
> > Would anyone volunteer to file a bug report?
>
> Me! Me! :)
>
>   https://issues.dlang.org/show_bug.cgi?id=23604
>
> Ali

Thanks a lot :D

Arredondo.