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| author | Dylan DPC <dylan.dpc@gmail.com> | 2020-05-22 21:45:01 +0200 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2020-05-22 21:45:01 +0200 |
| commit | 141ce5f2ad043efdf902d0d005b7a9bfa8cb63c4 (patch) | |
| tree | 19746f2ce7064656b14dd158429020b5e769cad4 /src/libcore | |
| parent | 3083ce7ab127dfd1cbb453810579ca827dcfd7bb (diff) | |
| parent | 9ff502029d379bebc50cf92a97f019fefba09d79 (diff) | |
Rollup merge of #72459 - yoshuawuyts:into-future, r=nikomatsakis
Add core::future::IntoFuture This patch reintroduces the `core::future::IntoFuture` trait. However unlike earlier PRs this patch does not integrate it into the `async/.await` lowering since that lead to performance regressions. By introducing the trait separately from the integration, the integration PR can be more narrowly scoped, and people can start trying out the `IntoFuture` trait today. Thanks heaps! cc/ @rust-lang/wg-async-foundations ## References - Original PR adding `IntoFuture` https://github.com/rust-lang/rust/pull/65244 - Open issue to re-land `IntoFuture` (assigned to me) https://github.com/rust-lang/rust/issues/67982 - Tracking issue for `IntoFuture` https://github.com/rust-lang/rust/issues/67644
Diffstat (limited to 'src/libcore')
| -rw-r--r-- | src/libcore/future/into_future.rs | 27 | ||||
| -rw-r--r-- | src/libcore/future/mod.rs | 4 |
2 files changed, 31 insertions, 0 deletions
diff --git a/src/libcore/future/into_future.rs b/src/libcore/future/into_future.rs new file mode 100644 index 00000000000..4020c254446 --- /dev/null +++ b/src/libcore/future/into_future.rs @@ -0,0 +1,27 @@ +use crate::future::Future; + +/// Conversion into a `Future`. +#[unstable(feature = "into_future", issue = "67644")] +pub trait IntoFuture { + /// The output that the future will produce on completion. + #[unstable(feature = "into_future", issue = "67644")] + type Output; + + /// Which kind of future are we turning this into? + #[unstable(feature = "into_future", issue = "67644")] + type Future: Future<Output = Self::Output>; + + /// Creates a future from a value. + #[unstable(feature = "into_future", issue = "67644")] + fn into_future(self) -> Self::Future; +} + +#[unstable(feature = "into_future", issue = "67644")] +impl<F: Future> IntoFuture for F { + type Output = F::Output; + type Future = F; + + fn into_future(self) -> Self::Future { + self + } +} diff --git a/src/libcore/future/mod.rs b/src/libcore/future/mod.rs index b5a102916a0..6f6009b47e6 100644 --- a/src/libcore/future/mod.rs +++ b/src/libcore/future/mod.rs @@ -10,12 +10,16 @@ use crate::{ }; mod future; +mod into_future; mod pending; mod ready; #[stable(feature = "futures_api", since = "1.36.0")] pub use self::future::Future; +#[unstable(feature = "into_future", issue = "67644")] +pub use into_future::IntoFuture; + #[unstable(feature = "future_readiness_fns", issue = "70921")] pub use pending::{pending, Pending}; #[unstable(feature = "future_readiness_fns", issue = "70921")] |