pub fn join_all<I>(iter: I) -> JoinAll<I::Item>
where
    I: IntoIterator,
    I::Item: Future,
{
    let iter = iter.into_iter();

    #[cfg(futures_no_atomic_cas)]
    {
        let kind =
            JoinAllKind::Small { elems: iter.map(MaybeDone::Future).collect::<Box<[_]>>().into() };

        assert_future::<Vec<<I::Item as Future>::Output>, _>(JoinAll { kind })
    }

    #[cfg(not(futures_no_atomic_cas))]
    {
        let kind = match iter.size_hint().1 {
            Some(max) if max <= SMALL => JoinAllKind::Small {
                elems: iter.map(MaybeDone::Future).collect::<Box<[_]>>().into(),
            },
            _ => JoinAllKind::Big { fut: iter.collect::<FuturesOrdered<_>>().collect() },
        };

        assert_future::<Vec<<I::Item as Future>::Output>, _>(JoinAll { kind })
    }
}
/// 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`][crate::stream::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
///
/// ```
/// # futures::executor::block_on(async {
/// 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]);
/// # });
/// ```
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` 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.
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 ` 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 .
pub fn join_all<I>(iter: I) -> JoinAll<I::Item>
where
    I: IntoIterator,
    I::Item: Future,
{
    let iter = iter.into_iter();
    #[cfg(futures_no_atomic_cas)]
    {
        let kind =
            JoinAllKind::Small { elems: iter.map(MaybeDone::Future).collect::<Box<[_]>>().into() };
        assert_future::<Vec<<I::Item as Future>::Output>, _>(JoinAll { kind })
    }
    #[cfg(not(futures_no_atomic_cas))]
    {
        let kind = match iter.size_hint().1 {
            Some(max) if max <= SMALL => JoinAllKind::Small {
                elems: iter.map(MaybeDone::Future).collect::<Box<[_]>>().into(),
            },
            _ => JoinAllKind::Big { fut: iter.collect::<FuturesOrdered<_>>().collect() },
        };
        assert_future::<Vec<<I::Item as Future>::Output>, _>(JoinAll { kind })
    }
}
pub fn join_all < I > ( iter : I ) -> JoinAll < I :: Item > where I : IntoIterator , I :: Item : Future , { let iter = iter . into_iter ( ) ; # [ cfg ( futures_no_atomic_cas ) ] { let kind = JoinAllKind :: Small { elems : iter . map ( MaybeDone :: Future ) . collect :: < Box < [ _ ] > > ( ) . into ( ) } ; assert_future :: < Vec < < I :: Item as Future > :: Output > , _ > ( JoinAll { kind } ) } # [ cfg ( not ( futures_no_atomic_cas ) ) ] { let kind = match iter . size_hint ( ) . 1 { Some ( max ) if max <= SMALL => JoinAllKind :: Small { elems : iter . map ( MaybeDone :: Future ) . collect :: < Box < [ _ ] > > ( ) . into ( ) , } , _ => JoinAllKind :: Big { fut : iter . collect :: < FuturesOrdered < _ > > ( ) . collect ( ) } , } ; assert_future :: < Vec < < I :: Item as Future > :: Output > , _ > ( JoinAll { kind } ) } }
Creates a future which represents a collection of the outputs of the futures
given.
Creates a future which represents a collection of the outputs of the futures given .
iter
I
iter
I
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`][crate::stream::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.
` 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 ` ] [ crate :: stream :: 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
None
futures::executor::block_on(async {
None
});
None