Function async_scoped::scope_and_iterate

pub unsafe async fn scope_and_iterate<'a, T: Send + 'static, R, F: FnOnce(&mut Scope<'a, T>) -> R, G: FnMut(T) -> H, H: Future<Output = ()>>(
    f: F, 
    g: G
) -> R

An asynchronous function that creates a scope and immediately awaits the stream, and sends it through an FnMut (using futures::StreamExt::for_each). It takes two args, the first that spawns the futures, and the second is the function to call on the stream. This macro must be invoked within an async block.

Safety

This macro is not completely safe: please see https://www.reddit.com/r/rust/comments/ee3vsu/asyncscoped_spawn_non_static_futures_with_asyncstd/fbpis3c?utm_source=share&utm_medium=web2x The caller must ensure the enclosing async block (and it's stack) does not collapse before the macro completes driving the stream. However, unless the enclosing future gets forgotten, the implementation will still panic when the returned future is dropped without being fully driven.