Initial implementation of when_all_range (incomplete)

[maikel]

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[lixin-wei]

Oh this is exactly what I need!

Is this planning to go into the C++ standard? Or it's only a stdexec's own utils?

[ericniebler]

@lixin-wei it will not be in c++26. i don't currently have plans to write a proposal for when_all_range for c++29. maybe you would like to try?

[lixin-wei]

@ericniebler I'm happy to have I try! I haven't written any proposal before, would you please give me a bit guide, telling me what sections you'd like to see in the proposal? I'll fill the details according to your catalogue.

[ericniebler]

@lixin-wei i would be happy to help. you can structure you paper like https://isocpp.org/files/papers/P3284R4.html, which proposes to add some algorithms to std::execution. the source for this paper is at https://github.com/ericniebler/wg21/blob/main/P3284/P3284.md. i use @mpark's pandoc framework. you can find the documentation for it here: https://github.com/mpark/wg21

[lixin-wei]

@ericniebler Thank you so much for the guide. I've written a basic veriosn: Rendered PDF / source code. Would you pls have a look when you have time?

And may I ask you 2 more questions?

1. Should I provide a complete wording for the standard now? I find it's not trivial, when_all's spec is very long, should I make a similar copy for when_all_range, which will mostly differ in the wording of impls-for<when_all_t>?
2. What's the next steps? How can I get an official number(PXXXX) for this proposal? Should I send to the std-proposal mailing list as this page says. Or it's enough to review with you?

[lixin-wei]

@ericniebler @maikel I wonder are you still planing to finish this PR? If not I can help. Can't wait to use it :)

[RobertLeahy]

Note that when_all_range is the topic of this C++Now talk.

[lixin-wei]

@RobertLeahy Excellent talk! learned a lot from it, thanks for your sharing! So will you take over this?