pub fn join_all<I>(iter: I) -> JoinAll<<I as IntoIterator>::Item>ⓘNotable traits for JoinAll<F>impl<F> Future for JoinAll<F>where
F: Future, type Output = Vec<<F as Future>::Output, Global>;where
I: IntoIterator,
<I as IntoIterator>::Item: Future,Expand description
Creates a future which represents a collection of the outputs of the futures given.
The returned future will drive execution for all of its underlying futures,
collecting the results into a destination Vec<T> in the same order as they
were provided.
This function is only available when the std or alloc feature of this
library is activated, and it is activated by default.
See Also
join_all will switch to the more powerful FuturesOrdered for performance
reasons if the number of futures is large. You may want to look into using it or
it’s counterpart FuturesUnordered directly.
Some examples for additional functionality provided by these are:
-
Adding new futures to the set even after it has been started.
-
Only polling the specific futures that have been woken. In cases where you have a lot of futures this will result in much more efficient polling.
Examples
use futures::future::join_all;
async fn foo(i: u32) -> u32 { i }
let futures = vec![foo(1), foo(2), foo(3)];
assert_eq!(join_all(futures).await, [1, 2, 3]);