For reference, SortedRange.release is documented as such:

"Releases the controlled range and returns it."

Wow thanks! I love functions that are named exactly as what they do ;-) Seriously though, I still don't know what it is that it does, and why and when it should be done, and when not.

What happens when a range is released?
What happens if a range is not released?
What happens if a range is released more than once?

And what does "controlled" imply here? In what way has SortedRange control over the underlaying data? What can I do and what can't I do to the underlying data as long as SortedRange has control?

My failure to understand this function makes me fear I don't understand SortedRange at all, and thereby don't understand how to use algorithm.sorting properly.

Thanks!

-- Bastiaan.

On Friday, 23 April 2021 at 17:35:13 UTC, Bastiaan Veelo wrote:

I had to look at the source to figure this out. Fortunately, the source is pretty simple:

https://phobos.dpldocs.info/source/std.range.d.html#L10833

Turns out, it just calls core.lifetime.move. So I guess when the docs say "control", what they are really talking about is ownership.

Practically speaking, this means that in generic code, we should avoid using a SortedRange after calling release, since we do not know whether the range is owning or non-owning w.r.t. the underlying data.

On Friday, 23 April 2021 at 18:35:25 UTC, Paul Backus wrote:

Thanks. There is no word in the documentation about when SortedRange would or would not be owning data, though, and hence when release would be appropriate to call. To me release seems to be calling std.algorithm.mutation.move , but it is probably very similar to core.lifetime.move.

In case the underlying data is a slice, I think we end up at https://phobos.dpldocs.info/source/std.algorithm.mutation.d.html#L1459, which I can't see accomplishes anything in this example (except returning the slice that went in):

int[] array = [ 1, 2, 3, 4 ];

// sort in descending order
array.sort!("a > b");
writeln(array); // [4, 3, 2, 1]

// sort in ascending order
array.sort();
writeln(array); // [1, 2, 3, 4]

// sort with reusable comparator and chain
alias myComp = (x, y) => x > y;
writeln(array.sort!(myComp).release); // [4, 3, 2, 1]

-- Bastiaan.

On Friday, 23 April 2021 at 21:34:39 UTC, Steven Schveighoffer wrote:

Understood, thanks.

--Bastiaan.