Extend the book's async page to show multiple calls to rust::Fn producing a stream #861
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dtolnay
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Aug 7, 2025
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| done(*ctx, std::move(res)); | ||
| done(*ctx, std::move(res)); | ||
| done(*ctx, std::move(res)); |
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Are you able to share some code structure that is more illustrative of how these res values would be obtained asynchronously in C++? As is, this example looks like it is just synchronously sending 3 values, which would not make sense to treat as futures::Stream in Rust. And something like co_await arg->next() does not work because this function is not a coroutine.
I am not familiar enough with streaming APIs in C++ to tell from this example how it would translate to usable real-world code.
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As documented in #856 this is a small edit to the async page to show returning streaming values by repeatedly executing a
rust::FnIf you don't feel like this would fit in with the goals of the book feel free to reject it. I thought I'd open the PR since having this myself would have helped me connect some dots of how the interaction between Rust and C++ works.