Initial draft

substrate/runtime-support/src/lib.rs

@@ -93,10 +93,16 @@ macro_rules! impl_outer_event {
 		$(#[$attr])*
 		#[allow(non_camel_case_types)]
 		pub enum $name {
+			system($crate::system::Event),
 			$(
 				$module($module::Event<$trait>),
 			)*
 		}
+		impl From<$crate::system::Event> for $name {
+			fn from(x: $create::system::Event) -> Self {
+				$name::system(x)
+			}
+		}
 		$(
 			impl From<$module::Event<$trait>> for $name {
 				fn from(x: $module::Event<$trait>) -> Self {

substrate/runtime/executive/src/lib.rs

@@ -88,7 +88,7 @@ pub struct Executive<
 	Lookup,
 	Payment,
 	Finalisation,
->(PhantomData<(System, Block, Lookup, Payment, Finalisation)>);
+>(PhantomData<(System, Block, Lookup, Payment, Event, Finalisation)>);
 
 impl<
 	Address,
@@ -205,7 +205,7 @@ impl<
 		// decode parameters and dispatch
 		let r = xt.apply();
 
-		<system::Module<System>>::note_applied_extrinsic();
+		<system::Module<System>>::note_applied_extrinsic(&r);
 
 		r.map(|_| internal::ApplyOutcome::Success).or_else(|e| Ok(internal::ApplyOutcome::Fail(e)))
 	}

substrate/runtime/system/src/lib.rs

@@ -83,7 +83,7 @@ pub trait Trait: Eq + Clone {
 		Hash = Self::Hash,
 		Digest = Self::Digest
 	>;
-	type Event: Parameter + Member;
+	type Event: Parameter + Member + From<Event>;
 }
 
 decl_module! {
@@ -110,6 +110,18 @@ pub struct EventRecord<E: Parameter + Member> {
 	pub event: E,
 }
 
+/// Event for the system module. 
+pub enum Event {
+	/// An extrinsic completed successfully.
+	ExtrinsicSuccess,
+	/// An extrinsic failed.
+	ExtrinsicFailed,
+}
+
+impl<N> From<RawEvent<N>> for () {
+	fn from(_: RawEvent<N>) -> () { () }
+}
+
 decl_storage! {
 	trait Store for Module<T: Trait> as System {
 
@@ -230,7 +242,12 @@ impl<T: Trait> Module<T> {
 	}
 
 	/// To be called immediately after an extrinsic has been applied.
-	pub fn note_applied_extrinsic() {
+	pub fn note_applied_extrinsic(r: &Result<(), &'static str>) {
+		Self::deposit_event(r
+			.map(|_| Event::ExtrinsicSuccess)
+			.map_err(|_| Event::ExtrinsicFailed)
+			.into()
+		);
 		<ExtrinsicIndex<T>>::put(<ExtrinsicIndex<T>>::get().unwrap_or_default() + 1u32);
 	}