Remove Container: Clone + 'static

Remove the requirement that all Container implementations are Clone and
'static. This makes implementing types simpler that depend on Container,
and requires us to explicitly mark various places as `Data` such that they
comply with Timely's type requirements.

Signed-off-by: Moritz Hoffmann <[email protected]>

Author: antiguru

container/src/columnation.rs

@@ -314,7 +314,7 @@ mod container {
 
     use crate::columnation::{Columnation, TimelyStack};
 
-    impl<T: Columnation + 'static> Container for TimelyStack<T> {
+    impl<T: Columnation> Container for TimelyStack<T> {
         type ItemRef<'a> = &'a T where Self: 'a;
         type Item<'a> = &'a T where Self: 'a;
 
@@ -330,13 +330,13 @@ mod container {
             TimelyStack::clear(self)
         }
 
-        type Iter<'a> = std::slice::Iter<'a, T>;
+        type Iter<'a> = std::slice::Iter<'a, T> where Self: 'a;
 
         fn iter(&self) -> Self::Iter<'_> {
             self.deref().iter()
         }
 
-        type DrainIter<'a> = std::slice::Iter<'a, T>;
+        type DrainIter<'a> = std::slice::Iter<'a, T> where Self: 'a;
 
         fn drain(&mut self) -> Self::DrainIter<'_> {
             (*self).iter()

container/src/lib.rs

@@ -16,8 +16,7 @@ pub mod flatcontainer;
 /// We require the container to be cloneable to enable efficient copies when providing references
 /// of containers to operators. Care must be taken that the type's `clone_from` implementation
 /// is efficient (which is not necessarily the case when deriving `Clone`.)
-/// TODO: Don't require `Container: Clone`
-pub trait Container: Default + Clone + 'static {
+pub trait Container: Default {
     /// The type of elements when reading non-destructively from the container.
     type ItemRef<'a> where Self: 'a;
 
@@ -42,13 +41,13 @@ pub trait Container: Default + Clone + 'static {
     fn clear(&mut self);
 
     /// Iterator type when reading from the container.
-    type Iter<'a>: Iterator<Item=Self::ItemRef<'a>>;
+    type Iter<'a>: Iterator<Item=Self::ItemRef<'a>> where Self: 'a;
 
     /// Returns an iterator that reads the contents of this container.
     fn iter(&self) -> Self::Iter<'_>;
 
     /// Iterator type when draining the container.
-    type DrainIter<'a>: Iterator<Item=Self::Item<'a>>;
+    type DrainIter<'a>: Iterator<Item=Self::Item<'a>> where Self: 'a;
 
     /// Returns an iterator that drains the contents of this container.
     /// Drain leaves the container in an undefined state.
@@ -83,7 +82,7 @@ pub trait PushContainer: Container {
     fn reserve(&mut self, additional: usize);
 }
 
-impl<T: Clone + 'static> Container for Vec<T> {
+impl<T> Container for Vec<T> {
     type ItemRef<'a> = &'a T where T: 'a;
     type Item<'a> = T where T: 'a;
 
@@ -97,13 +96,13 @@ impl<T: Clone + 'static> Container for Vec<T> {
 
     fn clear(&mut self) { Vec::clear(self) }
 
-    type Iter<'a> = std::slice::Iter<'a, T>;
+    type Iter<'a> = std::slice::Iter<'a, T> where Self: 'a;
 
     fn iter(&self) -> Self::Iter<'_> {
         self.as_slice().iter()
     }
 
-    type DrainIter<'a> = std::vec::Drain<'a, T>;
+    type DrainIter<'a> = std::vec::Drain<'a, T> where Self: 'a;
 
     fn drain(&mut self) -> Self::DrainIter<'_> {
         self.drain(..)
@@ -165,13 +164,13 @@ mod rc {
             }
         }
 
-        type Iter<'a> = T::Iter<'a>;
+        type Iter<'a> = T::Iter<'a> where Self: 'a;
 
         fn iter(&self) -> Self::Iter<'_> {
             self.deref().iter()
         }
 
-        type DrainIter<'a> = T::Iter<'a>;
+        type DrainIter<'a> = T::Iter<'a> where Self: 'a;
 
         fn drain(&mut self) -> Self::DrainIter<'_> {
             self.iter()
@@ -206,13 +205,13 @@ mod arc {
             }
         }
 
-        type Iter<'a> = T::Iter<'a>;
+        type Iter<'a> = T::Iter<'a> where Self: 'a;
 
         fn iter(&self) -> Self::Iter<'_> {
             self.deref().iter()
         }
 
-        type DrainIter<'a> = T::Iter<'a>;
+        type DrainIter<'a> = T::Iter<'a> where Self: 'a;
 
         fn drain(&mut self) -> Self::DrainIter<'_> {
             self.iter()
@@ -232,7 +231,7 @@ pub trait PushPartitioned: PushContainer {
         F: FnMut(usize, &mut Self);
 }
 
-impl<T: PushContainer + 'static> PushPartitioned for T where for<'a> T::Item<'a>: PushInto<T> {
+impl<T: PushContainer> PushPartitioned for T where for<'a> T::Item<'a>: PushInto<T> {
     fn push_partitioned<I, F>(&mut self, buffers: &mut [Self], mut index: I, mut flush: F)
     where
         for<'a> I: FnMut(&Self::Item<'a>) -> usize,

timely/src/dataflow/channels/pact.rs

@@ -9,9 +9,9 @@
 
 use std::{fmt::{self, Debug}, marker::PhantomData};
 
-use crate::Container;
+use crate::{Container, ExchangeData};
 use crate::communication::allocator::thread::{ThreadPusher, ThreadPuller};
-use crate::communication::{Push, Pull, Data};
+use crate::communication::{Push, Pull};
 use crate::container::PushPartitioned;
 use crate::dataflow::channels::pushers::Exchange as ExchangePusher;
 use crate::dataflow::channels::{Bundle, Message};
@@ -33,7 +33,7 @@ pub trait ParallelizationContract<T, C> {
 #[derive(Debug)]
 pub struct Pipeline;
 
-impl<T: 'static, C: Container> ParallelizationContract<T, C> for Pipeline {
+impl<T: 'static, C: Container + 'static> ParallelizationContract<T, C> for Pipeline {
     type Pusher = LogPusher<T, C, ThreadPusher<Bundle<T, C>>>;
     type Puller = LogPuller<T, C, ThreadPuller<Bundle<T, C>>>;
     fn connect<A: AsWorker>(self, allocator: &mut A, identifier: usize, address: &[usize], logging: Option<Logger>) -> (Self::Pusher, Self::Puller) {
@@ -66,7 +66,7 @@ where
 // Exchange uses a `Box<Pushable>` because it cannot know what type of pushable will return from the allocator.
 impl<T: Timestamp, C, H: 'static> ParallelizationContract<T, C> for ExchangeCore<C, H>
 where
-    C: Data + PushPartitioned,
+    C: PushPartitioned + ExchangeData,
     for<'a> H: FnMut(&C::Item<'a>) -> u64
 {
     type Pusher = ExchangePusher<T, C, LogPusher<T, C, Box<dyn Push<Bundle<T, C>>>>, H>;

timely/src/dataflow/channels/pushers/exchange.rs

@@ -3,7 +3,7 @@
 use crate::communication::Push;
 use crate::container::PushPartitioned;
 use crate::dataflow::channels::{Bundle, Message};
-use crate::{Container, Data};
+use crate::Data;
 
 // TODO : Software write combining
 /// Distributes records among target pushees according to a distribution function.
@@ -44,9 +44,9 @@ where
     }
 }
 
-impl<T: Eq+Data, C: Container, P: Push<Bundle<T, C>>, H, > Push<Bundle<T, C>> for Exchange<T, C, P, H>
+impl<T: Eq+Data, C, P: Push<Bundle<T, C>>, H, > Push<Bundle<T, C>> for Exchange<T, C, P, H>
 where
-    C: PushPartitioned,
+    C: PushPartitioned+Data,
     for<'a> H: FnMut(&C::Item<'a>) -> u64
 {
     #[inline(never)]

timely/src/dataflow/channels/pushers/tee.rs

@@ -17,7 +17,7 @@ pub struct Tee<T, C> {
     shared: PushList<T, C>,
 }
 
-impl<T: Data, C: Container> Push<Bundle<T, C>> for Tee<T, C> {
+impl<T: Data, C: Container+Data> Push<Bundle<T, C>> for Tee<T, C> {
     #[inline]
     fn push(&mut self, message: &mut Option<Bundle<T, C>>) {
         let mut pushers = self.shared.borrow_mut();

timely/src/dataflow/operators/branch.rs

@@ -94,7 +94,7 @@ pub trait BranchWhen<T>: Sized {
     fn branch_when(&self, condition: impl Fn(&T) -> bool + 'static) -> (Self, Self);
 }
 
-impl<S: Scope, C: Container> BranchWhen<S::Timestamp> for StreamCore<S, C> {
+impl<S: Scope, C: Container + Data> BranchWhen<S::Timestamp> for StreamCore<S, C> {
     fn branch_when(&self, condition: impl Fn(&S::Timestamp) -> bool + 'static) -> (Self, Self) {
         let mut builder = OperatorBuilder::new("Branch".to_owned(), self.scope());
 

timely/src/dataflow/operators/core/capture/capture.rs

@@ -10,14 +10,14 @@ use crate::dataflow::channels::pact::Pipeline;
 use crate::dataflow::channels::pullers::Counter as PullCounter;
 use crate::dataflow::operators::generic::builder_raw::OperatorBuilder;
 
-use crate::Container;
+use crate::{Container, Data};
 use crate::progress::ChangeBatch;
 use crate::progress::Timestamp;
 
 use super::{Event, EventPusher};
 
 /// Capture a stream of timestamped data for later replay.
-pub trait Capture<T: Timestamp, C: Container> {
+pub trait Capture<T: Timestamp, C: Container+Data> {
     /// Captures a stream of timestamped data for later replay.
     ///
     /// # Examples
@@ -113,7 +113,7 @@ pub trait Capture<T: Timestamp, C: Container> {
     }
 }
 
-impl<S: Scope, C: Container> Capture<S::Timestamp, C> for StreamCore<S, C> {
+impl<S: Scope, C: Container + Data> Capture<S::Timestamp, C> for StreamCore<S, C> {
     fn capture_into<P: EventPusher<S::Timestamp, C>+'static>(&self, mut event_pusher: P) {
 
         let mut builder = OperatorBuilder::new("Capture".to_owned(), self.scope());

timely/src/dataflow/operators/core/capture/replay.rs

@@ -46,7 +46,7 @@ use crate::progress::Timestamp;
 
 use super::Event;
 use super::event::EventIterator;
-use crate::Container;
+use crate::{Container, Data};
 
 /// Replay a capture stream into a scope with the same timestamp.
 pub trait Replay<T: Timestamp, C> : Sized {
@@ -62,7 +62,7 @@ pub trait Replay<T: Timestamp, C> : Sized {
     fn replay_core<S: Scope<Timestamp=T>>(self, scope: &mut S, period: Option<std::time::Duration>) -> StreamCore<S, C>;
 }
 
-impl<T: Timestamp, C: Container, I> Replay<T, C> for I
+impl<T: Timestamp, C: Container + Data, I> Replay<T, C> for I
 where
     I : IntoIterator,
     <I as IntoIterator>::Item: EventIterator<T, C>+'static,

timely/src/dataflow/operators/core/concat.rs

@@ -1,7 +1,7 @@
 //! Merges the contents of multiple streams.
 
 
-use crate::Container;
+use crate::{Container, Data};
 use crate::dataflow::channels::pact::Pipeline;
 use crate::dataflow::{StreamCore, Scope};
 
@@ -23,7 +23,7 @@ pub trait Concat<G: Scope, C: Container> {
     fn concat(&self, _: &StreamCore<G, C>) -> StreamCore<G, C>;
 }
 
-impl<G: Scope, C: Container> Concat<G, C> for StreamCore<G, C> {
+impl<G: Scope, C: Container + Data> Concat<G, C> for StreamCore<G, C> {
     fn concat(&self, other: &StreamCore<G, C>) -> StreamCore<G, C> {
         self.scope().concatenate([self.clone(), other.clone()])
     }
@@ -52,7 +52,7 @@ pub trait Concatenate<G: Scope, C: Container> {
         I: IntoIterator<Item=StreamCore<G, C>>;
 }
 
-impl<G: Scope, C: Container> Concatenate<G, C> for StreamCore<G, C> {
+impl<G: Scope, C: Container + Data> Concatenate<G, C> for StreamCore<G, C> {
     fn concatenate<I>(&self, sources: I) -> StreamCore<G, C>
     where
         I: IntoIterator<Item=StreamCore<G, C>>
@@ -62,7 +62,7 @@ impl<G: Scope, C: Container> Concatenate<G, C> for StreamCore<G, C> {
     }
 }
 
-impl<G: Scope, C: Container> Concatenate<G, C> for G {
+impl<G: Scope, C: Container + Data> Concatenate<G, C> for G {
     fn concatenate<I>(&self, sources: I) -> StreamCore<G, C>
     where
         I: IntoIterator<Item=StreamCore<G, C>>

timely/src/dataflow/operators/core/enterleave.rs

@@ -103,7 +103,7 @@ pub trait Leave<G: Scope, C: Container> {
     fn leave(&self) -> StreamCore<G, C>;
 }
 
-impl<'a, G: Scope, C: Clone+Container, T: Timestamp+Refines<G::Timestamp>> Leave<G, C> for StreamCore<Child<'a, G, T>, C> {
+impl<'a, G: Scope, C: Container+Data, T: Timestamp+Refines<G::Timestamp>> Leave<G, C> for StreamCore<Child<'a, G, T>, C> {
     fn leave(&self) -> StreamCore<G, C> {
 
         let scope = self.scope();
@@ -130,14 +130,14 @@ impl<'a, G: Scope, C: Clone+Container, T: Timestamp+Refines<G::Timestamp>> Leave
 }
 
 
-struct IngressNub<TOuter: Timestamp, TInner: Timestamp+Refines<TOuter>, TContainer: Container> {
+struct IngressNub<TOuter: Timestamp, TInner: Timestamp+Refines<TOuter>, TContainer: Container+Data> {
     targets: Counter<TInner, TContainer, Tee<TInner, TContainer>>,
     phantom: ::std::marker::PhantomData<TOuter>,
     activator: crate::scheduling::Activator,
     active: bool,
 }
 
-impl<TOuter: Timestamp, TInner: Timestamp+Refines<TOuter>, TContainer: Container> Push<Bundle<TOuter, TContainer>> for IngressNub<TOuter, TInner, TContainer> {
+impl<TOuter: Timestamp, TInner: Timestamp+Refines<TOuter>, TContainer: Container+Data> Push<Bundle<TOuter, TContainer>> for IngressNub<TOuter, TInner, TContainer> {
     fn push(&mut self, element: &mut Option<Bundle<TOuter, TContainer>>) {
         if let Some(message) = element {
             let outer_message = message.as_mut();