builds with non-clone 'any'

Cargo.lock

@@ -1368,6 +1368,15 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "smolset"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f5a73542b3021a40b49f29e6ce18b65ff38dbafbf7df8be0fa9f9305305f62ee"
+dependencies = [
+ "smallvec",
+]
+
 [[package]]
 name = "socket2"
 version = "0.3.19"
@@ -1779,6 +1788,7 @@ dependencies = [
 name = "yuurei"
 version = "0.1.0"
 dependencies = [
+ "cfg-if 1.0.0",
  "color-eyre",
  "cryptohelpers",
  "difference",
@@ -1793,6 +1803,7 @@ dependencies = [
  "serde",
  "sha2",
  "smallvec",
+ "smolset",
  "tokio",
  "uuid",
  "warp",

Cargo.toml

@@ -11,6 +11,7 @@ default = ["nightly"]
 nightly = ["smallvec/const_generics"]
 
 [dependencies]
+cfg-if = "1.0.0"
 color-eyre = {version = "0.5.10", default-features=false}
 cryptohelpers = {version = "1.7.1", features=["full"]}
 difference = "2.0.0"
@@ -25,6 +26,7 @@ pretty_env_logger = "0.4.0"
 serde = {version = "1.0.118", features=["derive"]}
 sha2 = "0.9.2"
 smallvec = {version = "1.6.0", features= ["union", "serde", "write"]}
+smolset = "1.1.0"
 tokio = {version = "0.2", features=["full"] } 
 uuid = {version = "0.8.1", features=["v4","serde"]}
 warp = "0.2.5"

src/ext.rs

@@ -578,3 +578,80 @@ impl Clone for DynCloneable
 
 }
 
+mod maybe_iter
+{
+    #[derive(Debug, Clone)]
+    enum Inner<I, T>
+    {
+	Some(I),
+	One(std::iter::Once<T>),
+	None,
+    }
+    /// An iterator that may yield 0, 1, or more values.
+    #[derive(Debug, Clone)]
+    #[repr(transparent)]
+    pub struct MaybeIter<I, T>(Inner<I, T>);
+
+    impl<I, T> MaybeIter<I, T>
+    where I: Iterator<Item=T>
+    {
+	/// Create a single element iterator
+	pub fn one<U: Into<T>>(from: U) -> Self
+	{
+	    Self(Inner::One(std::iter::once(from.into())))
+	}
+	/// Create a new instance from an iterator
+	pub fn many<U: IntoIterator<IntoIter = I, Item=T>>(from: U) -> Self
+	{
+	    Self(Inner::Some(from.into_iter()))
+	}
+	/// Create a new instance that yields 0 items
+	#[inline(always)] pub fn none() -> Self
+	{
+	    Self(Inner::None)
+	}
+    }
+
+    impl<I, T, U> From<Option<U>> for MaybeIter<I, T>
+    where I: Iterator<Item=T>,
+	  U: IntoIterator<IntoIter=I, Item=T>
+    {
+	fn from(from: Option<U>) -> Self
+	{
+	    match from {
+		Some(many) => Self::many(many),
+		_ => Self::none()
+	    }
+	}
+    }
+
+    
+    impl<I, T> Iterator for MaybeIter<I, T>
+    where I: Iterator<Item=T>
+    {
+	type Item = T;
+	fn next(&mut self) -> Option<Self::Item>
+	{
+	    match &mut self.0 {
+		Inner::Some(x) => x.next(),
+		Inner::One(x) => x.next(),
+		Inner::None => None,
+	    }
+	}
+
+	#[inline] fn size_hint(&self) -> (usize, Option<usize>) {
+	    match &self.0
+	    {
+		Inner::One(c) => c.size_hint(),
+		Inner::Some(x) => x.size_hint(),
+		Inner::None => (0, Some(0))
+	    }
+	}
+    }
+
+    impl<T, I: Iterator<Item=T>> std::iter::FusedIterator for MaybeIter<I, T>
+    where I: std::iter::FusedIterator{}
+    impl<T, I: Iterator<Item=T>> ExactSizeIterator for MaybeIter<I, T>
+    where I: ExactSizeIterator{}
+}
+pub use maybe_iter::MaybeIter;

src/main.rs

@@ -8,6 +8,7 @@
 #[macro_use] extern crate lazy_static;
 #[macro_use] extern crate log;
 #[macro_use] extern crate mopa;
+#[macro_use] extern crate cfg_if;
 
 use std::convert::{TryFrom, TryInto};
 use color_eyre::{

src/state/service.rs

@@ -15,7 +15,7 @@ use crate::service::{
 use std::{error, fmt};
 use std::sync::Weak;
 use std::any::Any;
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap};
 
 
 id_type!(ServiceSubID; "Optional ID for filtering directed broadcast messages");
@@ -80,36 +80,16 @@ pub(super) struct Supervisor
 
 /// Object sent through the broadcast channel.
 ///
-/// These objects can be cloned and downcasted, but can also be atomically refcounted if that is more desireable.
+/// These objects can be cloned and downcasted, becaause they are  atomically refcounted if that is more desireable.
-///
+#[derive(Clone)]
-/// # Cloning
+pub struct ServiceEventObject(Arc<dyn Any + Send + Sync + 'static>);
-/// The implementation of `Clone` for this instance clones the inner object, not the refcount. Use `clone_ref()` to *just* clone the refcount.
-/// To downcast and clone the inner object without an extra `Arc` allocation, use `downcast_clone()` or `downcast().map(Clone::clone)`.
-pub struct ServiceEventObject(Arc<dyn AnyCloneable + Send + Sync + 'static>);
 shim_debug!(ServiceEventObject);
+
 /// A weak reference to a `ServiceEventObject`.
 #[derive(Clone)]
-pub struct ServiceEventObjectRef(Weak<dyn AnyCloneable + Send + Sync + 'static>);
+pub struct ServiceEventObjectRef(Weak<dyn Any + Send + Sync + 'static>);
 shim_debug!(ServiceEventObjectRef);
 
-/// Wrapper used when broadcasting to prevent useless inner object clones.
-#[derive(Debug)]
-struct EventObjectRefCloneWrap(ServiceEventObject);
-
-impl Clone for EventObjectRefCloneWrap
-{
-    fn clone(&self) -> Self {
-	Self(self.0.clone_ref())
-    }
-}
-
-impl Clone for ServiceEventObject
-{
-    fn clone(&self) -> Self {
-	Self(Arc::from(self.0.as_ref().clone_dyn()))
-    }
-}
-
 impl ServiceEventObjectRef
 {
     /// Try to upgrade to a concrete reference, and then clone the inner object.
@@ -135,12 +115,6 @@ impl ServiceEventObjectRef
 
 impl ServiceEventObject
 {
-    /// Get an owned reference counted handle to the object, without cloning the object itself.
-    pub fn clone_ref(&self) -> Self
-    {
-	Self(Arc::clone(&self.0))
-    }
-
     /// Get a weak reference counted handle to the object, without cloning the object itself.
     pub fn clone_weak(&self) -> ServiceEventObjectRef
     {
@@ -164,8 +138,11 @@ impl ServiceEventObject
     {
 	match Arc::downcast(self.0)
 	{
-	    Ok(v) => v,
+	    Ok(v) => match Arc::try_unwrap(v) {
-	    Err(e) => Self(e),
+		Ok(v) => Ok(v),
+		Err(s) => Err(Self(s)),
+	    },
+	    Err(e) => Err(Self(e)),
 	}
     }
 
@@ -176,14 +153,14 @@ impl ServiceEventObject
     }
 
     /// Try to downcast the object into a concrete type
-    #[inline] pub fn is<T: AnyCloneable  + Send + Sync + 'static>(&self) -> Option<&T>
+    #[inline] pub fn is<T: AnyCloneable  + Send + Sync + 'static>(&self) -> bool
     {
-	self.0.is()
+	self.0.as_ref().is::<T>()
     }
     /// Try to downcast the object into a concrete type
     #[inline] pub fn downcast_ref<T: AnyCloneable  + Send + Sync + 'static>(&self) -> Option<&T>
     {
-	self.0.downcast_ref()
+	self.0.as_ref().downcast_ref::<T>()
     }
 }
 
@@ -199,13 +176,23 @@ pub enum ServiceEventKind
     KeepAlive,
 }
 
+cfg_if!{
+    if #[cfg(debug_assertions)] {
+	/// Type used for directed array.
+	/// Currently testing `smolset` over eagerly allocating.
+	type SESet<T> = smolset::SmolSet<[T; 1]>;
+    } else {
+	type SESet<T> = std::collections::HashSet<T>;
+    }
+}
+
 /// An event outputted from a state service's broadcast stream
 #[derive(Debug, Clone)]
 pub struct ServiceEvent
 {
     kind: ServiceEventKind,
-    directed: Option<MaybeVec<ServiceSubID>>,
+    directed: Option<SESet<ServiceSubID>>,
-    obj: Option<EventObjectRefCloneWrap>,
+    obj: Option<ServiceEventObject>,
 }
 
 impl ServiceEvent
@@ -220,7 +207,7 @@ impl ServiceEvent
     pub fn is_directed_for(&self, whom: &ServiceSubID) -> bool
     {
 	if let Some(yes) = self.directed.as_ref() {
-	    yes == whom
+	    yes.contains(whom)
 	} else {
 	    false
 	}
@@ -234,25 +221,25 @@ impl ServiceEvent
     /// Check who this event is directed to.
     ///
     /// If it is not directed, an empty slice will be returned.
-    pub fn directed_to(&self) -> &[&ServiceSubID]
+    pub fn directed_to(&self) -> impl Iterator<Item = &'_ ServiceSubID> + '_
     {
 	match self.directed.as_ref()
 	{
-	    Some(yes) => &yes[..],
+	    Some(yes) => MaybeIter::many(yes.iter()),
-	    None => &[],
+	    None => MaybeIter::none(),
 	}
     }
 
     /// Get a reference to the object, if there is one.
     pub fn obj_ref(&self) -> Option<&ServiceEventObject>
     {
-	self.obj.as_ref().map(|x| x.0)
+	self.obj.as_ref()
     }
 
     /// Get a mutable reference to the object, if there is one.
     pub fn obj_mut(&mut self) -> Option<&mut ServiceEventObject>
     {
-	self.obj.as_mut().map(|x| x.0)
+	self.obj.as_mut()
     }
 
     /// Try to consume into the inner object. If there is no object, return self.
@@ -266,6 +253,7 @@ impl ServiceEvent
     }
 }
 
+
 impl From<ServiceEvent> for Option<ServiceEventObject>
 {
     #[inline] fn from(from: ServiceEvent) -> Self
@@ -282,7 +270,7 @@ impl TryFrom<ServiceEvent> for ServiceEventObject
     {
 	match from.obj
 	{
-	    Some(obj) => Ok(obj.0),
+	    Some(obj) => Ok(obj),
 	    None => Err(NoObjectError),
 	}
     }