Merge pull request 'remove uses of #[async_trait]' (#952) from remove-async-trait into mainHEADmain

Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/952

23 files changed, 40 insertions, 80 deletions

diff --git a/src/api/admin/api_server.rs b/src/api/admin/api_server.rs
index e39fa1ba..6f0c474f 100644
--- a/src/api/admin/api_server.rs
+++ b/src/api/admin/api_server.rs
@@ -2,7 +2,6 @@ use std::collections::HashMap;
 use std::sync::Arc;
 
 use argon2::password_hash::PasswordHash;
-use async_trait::async_trait;
 
 use http::header::{ACCESS_CONTROL_ALLOW_METHODS, ACCESS_CONTROL_ALLOW_ORIGIN, ALLOW};
 use hyper::{body::Incoming as IncomingBody, Request, Response, StatusCode};
@@ -221,7 +220,6 @@ impl AdminApiServer {
 	}
 }
 
-#[async_trait]
 impl ApiHandler for AdminApiServer {
 	const API_NAME: &'static str = "admin";
 	const API_NAME_DISPLAY: &'static str = "Admin";
diff --git a/src/api/common/Cargo.toml b/src/api/common/Cargo.toml
index 842662c4..5b9cf479 100644
--- a/src/api/common/Cargo.toml
+++ b/src/api/common/Cargo.toml
@@ -18,7 +18,6 @@ garage_model.workspace = true
 garage_table.workspace = true
 garage_util.workspace = true
 
-async-trait.workspace = true
 bytes.workspace = true
 chrono.workspace = true
 crypto-common.workspace = true
diff --git a/src/api/common/generic_server.rs b/src/api/common/generic_server.rs
index d92a3465..6ddc2ff2 100644
--- a/src/api/common/generic_server.rs
+++ b/src/api/common/generic_server.rs
@@ -4,8 +4,6 @@ use std::os::unix::fs::PermissionsExt;
 use std::sync::Arc;
 use std::time::Duration;
 
-use async_trait::async_trait;
-
 use futures::future::Future;
 use futures::stream::{futures_unordered::FuturesUnordered, StreamExt};
 
@@ -47,7 +45,6 @@ pub trait ApiError: std::error::Error + Send + Sync + 'static {
 	fn http_body(&self, garage_region: &str, path: &str) -> ErrorBody;
 }
 
-#[async_trait]
 pub trait ApiHandler: Send + Sync + 'static {
 	const API_NAME: &'static str;
 	const API_NAME_DISPLAY: &'static str;
@@ -56,11 +53,11 @@ pub trait ApiHandler: Send + Sync + 'static {
 	type Error: ApiError;
 
 	fn parse_endpoint(&self, r: &Request<IncomingBody>) -> Result<Self::Endpoint, Self::Error>;
-	async fn handle(
+	fn handle(
 		&self,
 		req: Request<IncomingBody>,
 		endpoint: Self::Endpoint,
-	) -> Result<Response<BoxBody<Self::Error>>, Self::Error>;
+	) -> impl Future<Output = Result<Response<BoxBody<Self::Error>>, Self::Error>> + Send;
 }
 
 pub struct ApiServer<A: ApiHandler> {
@@ -248,13 +245,11 @@ impl<A: ApiHandler> ApiServer<A> {
 
 // ==== helper functions ====
 
-#[async_trait]
 pub trait Accept: Send + Sync + 'static {
 	type Stream: AsyncRead + AsyncWrite + Send + Sync + 'static;
-	async fn accept(&self) -> std::io::Result<(Self::Stream, String)>;
+	fn accept(&self) -> impl Future<Output = std::io::Result<(Self::Stream, String)>> + Send;
 }
 
-#[async_trait]
 impl Accept for TcpListener {
 	type Stream = TcpStream;
 	async fn accept(&self) -> std::io::Result<(Self::Stream, String)> {
@@ -266,7 +261,6 @@ impl Accept for TcpListener {
 
 pub struct UnixListenerOn(pub UnixListener, pub String);
 
-#[async_trait]
 impl Accept for UnixListenerOn {
 	type Stream = UnixStream;
 	async fn accept(&self) -> std::io::Result<(Self::Stream, String)> {
diff --git a/src/api/k2v/Cargo.toml b/src/api/k2v/Cargo.toml
index d4e26efa..e3ebedca 100644
--- a/src/api/k2v/Cargo.toml
+++ b/src/api/k2v/Cargo.toml
@@ -19,7 +19,6 @@ garage_table.workspace = true
 garage_util = { workspace = true, features = [ "k2v" ] }
 garage_api_common.workspace = true
 
-async-trait.workspace = true
 base64.workspace = true
 err-derive.workspace = true
 tracing.workspace = true
diff --git a/src/api/k2v/api_server.rs b/src/api/k2v/api_server.rs
index 31e07762..eb276f5b 100644
--- a/src/api/k2v/api_server.rs
+++ b/src/api/k2v/api_server.rs
@@ -1,7 +1,5 @@
 use std::sync::Arc;
 
-use async_trait::async_trait;
-
 use hyper::{body::Incoming as IncomingBody, Method, Request, Response};
 use tokio::sync::watch;
 
@@ -48,7 +46,6 @@ impl K2VApiServer {
 	}
 }
 
-#[async_trait]
 impl ApiHandler for K2VApiServer {
 	const API_NAME: &'static str = "k2v";
 	const API_NAME_DISPLAY: &'static str = "K2V";
diff --git a/src/api/s3/Cargo.toml b/src/api/s3/Cargo.toml
index a1751c9f..387e45db 100644
--- a/src/api/s3/Cargo.toml
+++ b/src/api/s3/Cargo.toml
@@ -24,7 +24,6 @@ garage_api_common.workspace = true
 
 aes-gcm.workspace = true
 async-compression.workspace = true
-async-trait.workspace = true
 base64.workspace = true
 bytes.workspace = true
 chrono.workspace = true
diff --git a/src/api/s3/api_server.rs b/src/api/s3/api_server.rs
index ed71b108..bf48bba1 100644
--- a/src/api/s3/api_server.rs
+++ b/src/api/s3/api_server.rs
@@ -1,7 +1,5 @@
 use std::sync::Arc;
 
-use async_trait::async_trait;
-
 use hyper::header;
 use hyper::{body::Incoming as IncomingBody, Request, Response};
 use tokio::sync::watch;
@@ -70,7 +68,6 @@ impl S3ApiServer {
 	}
 }
 
-#[async_trait]
 impl ApiHandler for S3ApiServer {
 	const API_NAME: &'static str = "s3";
 	const API_NAME_DISPLAY: &'static str = "S3";
diff --git a/src/block/manager.rs b/src/block/manager.rs
index 40b177a2..537e1fc1 100644
--- a/src/block/manager.rs
+++ b/src/block/manager.rs
@@ -4,7 +4,6 @@ use std::sync::Arc;
 use std::time::Duration;
 
 use arc_swap::{ArcSwap, ArcSwapOption};
-use async_trait::async_trait;
 use bytes::Bytes;
 use rand::prelude::*;
 use serde::{Deserialize, Serialize};
@@ -688,7 +687,6 @@ impl BlockManager {
 	}
 }
 
-#[async_trait]
 impl StreamingEndpointHandler<BlockRpc> for BlockManager {
 	async fn handle(self: &Arc<Self>, mut message: Req<BlockRpc>, _from: NodeID) -> Resp<BlockRpc> {
 		match message.msg() {
diff --git a/src/garage/admin/mod.rs b/src/garage/admin/mod.rs
index e2468143..ea414b56 100644
--- a/src/garage/admin/mod.rs
+++ b/src/garage/admin/mod.rs
@@ -4,9 +4,11 @@ mod key;
 
 use std::collections::HashMap;
 use std::fmt::Write;
+use std::future::Future;
 use std::sync::Arc;
 
-use async_trait::async_trait;
+use futures::future::FutureExt;
+
 use serde::{Deserialize, Serialize};
 
 use format_table::format_table_to_string;
@@ -505,22 +507,25 @@ impl AdminRpcHandler {
 	}
 }
 
-#[async_trait]
 impl EndpointHandler<AdminRpc> for AdminRpcHandler {
-	async fn handle(
+	fn handle(
 		self: &Arc<Self>,
 		message: &AdminRpc,
 		_from: NodeID,
-	) -> Result<AdminRpc, Error> {
-		match message {
-			AdminRpc::BucketOperation(bo) => self.handle_bucket_cmd(bo).await,
-			AdminRpc::KeyOperation(ko) => self.handle_key_cmd(ko).await,
-			AdminRpc::LaunchRepair(opt) => self.handle_launch_repair(opt.clone()).await,
-			AdminRpc::Stats(opt) => self.handle_stats(opt.clone()).await,
-			AdminRpc::Worker(wo) => self.handle_worker_cmd(wo).await,
-			AdminRpc::BlockOperation(bo) => self.handle_block_cmd(bo).await,
-			AdminRpc::MetaOperation(mo) => self.handle_meta_cmd(mo).await,
-			m => Err(GarageError::unexpected_rpc_message(m).into()),
+	) -> impl Future<Output = Result<AdminRpc, Error>> + Send {
+		let self2 = self.clone();
+		async move {
+			match message {
+				AdminRpc::BucketOperation(bo) => self2.handle_bucket_cmd(bo).await,
+				AdminRpc::KeyOperation(ko) => self2.handle_key_cmd(ko).await,
+				AdminRpc::LaunchRepair(opt) => self2.handle_launch_repair(opt.clone()).await,
+				AdminRpc::Stats(opt) => self2.handle_stats(opt.clone()).await,
+				AdminRpc::Worker(wo) => self2.handle_worker_cmd(wo).await,
+				AdminRpc::BlockOperation(bo) => self2.handle_block_cmd(bo).await,
+				AdminRpc::MetaOperation(mo) => self2.handle_meta_cmd(mo).await,
+				m => Err(GarageError::unexpected_rpc_message(m).into()),
+			}
 		}
+		.boxed()
 	}
 }
diff --git a/src/garage/repair/online.rs b/src/garage/repair/online.rs
index 2c5227d2..47883f97 100644
--- a/src/garage/repair/online.rs
+++ b/src/garage/repair/online.rs
@@ -1,3 +1,4 @@
+use std::future::Future;
 use std::sync::Arc;
 use std::time::Duration;
 
@@ -93,17 +94,16 @@ pub async fn launch_online_repair(
 
 // ----
 
-#[async_trait]
 trait TableRepair: Send + Sync + 'static {
 	type T: TableSchema;
 
 	fn table(garage: &Garage) -> &Table<Self::T, TableShardedReplication>;
 
-	async fn process(
+	fn process(
 		&mut self,
 		garage: &Garage,
 		entry: <<Self as TableRepair>::T as TableSchema>::E,
-	) -> Result<bool, Error>;
+	) -> impl Future<Output = Result<bool, Error>> + Send;
 }
 
 struct TableRepairWorker<T: TableRepair> {
@@ -174,7 +174,6 @@ impl<R: TableRepair> Worker for TableRepairWorker<R> {
 
 struct RepairVersions;
 
-#[async_trait]
 impl TableRepair for RepairVersions {
 	type T = VersionTable;
 
@@ -221,7 +220,6 @@ impl TableRepair for RepairVersions {
 
 struct RepairBlockRefs;
 
-#[async_trait]
 impl TableRepair for RepairBlockRefs {
 	type T = BlockRefTable;
 
@@ -257,7 +255,6 @@ impl TableRepair for RepairBlockRefs {
 
 struct RepairMpu;
 
-#[async_trait]
 impl TableRepair for RepairMpu {
 	type T = MultipartUploadTable;
 
diff --git a/src/model/k2v/rpc.rs b/src/model/k2v/rpc.rs
index a1bf6ee0..821f4549 100644
--- a/src/model/k2v/rpc.rs
+++ b/src/model/k2v/rpc.rs
@@ -10,7 +10,6 @@ use std::convert::TryInto;
 use std::sync::{Arc, Mutex, MutexGuard};
 use std::time::{Duration, Instant};
 
-use async_trait::async_trait;
 use futures::stream::FuturesUnordered;
 use futures::StreamExt;
 use serde::{Deserialize, Serialize};
@@ -537,7 +536,6 @@ impl K2VRpcHandler {
 	}
 }
 
-#[async_trait]
 impl EndpointHandler<K2VRpc> for K2VRpcHandler {
 	async fn handle(self: &Arc<Self>, message: &K2VRpc, _from: NodeID) -> Result<K2VRpc, Error> {
 		match message {
diff --git a/src/net/Cargo.toml b/src/net/Cargo.toml
index 686aaaea..c0b47a6e 100644
--- a/src/net/Cargo.toml
+++ b/src/net/Cargo.toml
@@ -30,7 +30,6 @@ rand.workspace = true
 
 log.workspace = true
 arc-swap.workspace = true
-async-trait.workspace = true
 err-derive.workspace = true
 bytes.workspace = true
 cfg-if.workspace = true
diff --git a/src/net/client.rs b/src/net/client.rs
index 607dd173..20e1dacd 100644
--- a/src/net/client.rs
+++ b/src/net/client.rs
@@ -6,7 +6,6 @@ use std::sync::{Arc, Mutex};
 use std::task::Poll;
 
 use arc_swap::ArcSwapOption;
-use async_trait::async_trait;
 use bytes::Bytes;
 use log::{debug, error, trace};
 
@@ -220,7 +219,6 @@ impl ClientConn {
 
 impl SendLoop for ClientConn {}
 
-#[async_trait]
 impl RecvLoop for ClientConn {
 	fn recv_handler(self: &Arc<Self>, id: RequestID, stream: ByteStream) {
 		trace!("ClientConn recv_handler {}", id);
diff --git a/src/net/endpoint.rs b/src/net/endpoint.rs
index 3cafafeb..d46acc42 100644
--- a/src/net/endpoint.rs
+++ b/src/net/endpoint.rs
@@ -1,8 +1,9 @@
+use std::future::Future;
 use std::marker::PhantomData;
 use std::sync::Arc;
 
 use arc_swap::ArcSwapOption;
-use async_trait::async_trait;
+use futures::future::{BoxFuture, FutureExt};
 
 use crate::error::Error;
 use crate::message::*;
@@ -14,19 +15,17 @@ use crate::netapp::*;
 /// attached to the response..
 ///
 /// The handler object should be in an Arc, see `Endpoint::set_handler`
-#[async_trait]
 pub trait StreamingEndpointHandler<M>: Send + Sync
 where
 	M: Message,
 {
-	async fn handle(self: &Arc<Self>, m: Req<M>, from: NodeID) -> Resp<M>;
+	fn handle(self: &Arc<Self>, m: Req<M>, from: NodeID) -> impl Future<Output = Resp<M>> + Send;
 }
 
 /// If one simply wants to use an endpoint in a client fashion,
 /// without locally serving requests to that endpoint,
 /// use the unit type `()` as the handler type:
 /// it will panic if it is ever made to handle request.
-#[async_trait]
 impl<M: Message> EndpointHandler<M> for () {
 	async fn handle(self: &Arc<()>, _m: &M, _from: NodeID) -> M::Response {
 		panic!("This endpoint should not have a local handler.");
@@ -38,15 +37,13 @@ impl<M: Message> EndpointHandler<M> for () {
 /// This trait should be implemented by an object of your application
 /// that can handle a message of type `M`, in the cases where it doesn't
 /// care about attached stream in the request nor in the response.
-#[async_trait]
 pub trait EndpointHandler<M>: Send + Sync
 where
 	M: Message,
 {
-	async fn handle(self: &Arc<Self>, m: &M, from: NodeID) -> M::Response;
+	fn handle(self: &Arc<Self>, m: &M, from: NodeID) -> impl Future<Output = M::Response> + Send;
 }
 
-#[async_trait]
 impl<T, M> StreamingEndpointHandler<M> for T
 where
 	T: EndpointHandler<M>,
@@ -161,9 +158,8 @@ where
 
 pub(crate) type DynEndpoint = Box<dyn GenericEndpoint + Send + Sync>;
 
-#[async_trait]
 pub(crate) trait GenericEndpoint {
-	async fn handle(&self, req_enc: ReqEnc, from: NodeID) -> Result<RespEnc, Error>;
+	fn handle(&self, req_enc: ReqEnc, from: NodeID) -> BoxFuture<Result<RespEnc, Error>>;
 	fn drop_handler(&self);
 	fn clone_endpoint(&self) -> DynEndpoint;
 }
@@ -174,21 +170,23 @@ where
 	M: Message,
 	H: StreamingEndpointHandler<M>;
 
-#[async_trait]
 impl<M, H> GenericEndpoint for EndpointArc<M, H>
 where
 	M: Message,
 	H: StreamingEndpointHandler<M> + 'static,
 {
-	async fn handle(&self, req_enc: ReqEnc, from: NodeID) -> Result<RespEnc, Error> {
-		match self.0.handler.load_full() {
-			None => Err(Error::NoHandler),
-			Some(h) => {
-				let req = Req::from_enc(req_enc)?;
-				let res = h.handle(req, from).await;
-				Ok(res.into_enc()?)
+	fn handle(&self, req_enc: ReqEnc, from: NodeID) -> BoxFuture<Result<RespEnc, Error>> {
+		async move {
+			match self.0.handler.load_full() {
+				None => Err(Error::NoHandler),
+				Some(h) => {
+					let req = Req::from_enc(req_enc)?;
+					let res = h.handle(req, from).await;
+					Ok(res.into_enc()?)
+				}
 			}
 		}
+		.boxed()
 	}
 
 	fn drop_handler(&self) {
diff --git a/src/net/netapp.rs b/src/net/netapp.rs
index 77e55774..36c6fc88 100644
--- a/src/net/netapp.rs
+++ b/src/net/netapp.rs
@@ -5,7 +5,6 @@ use std::sync::{Arc, RwLock};
 use log::{debug, error, info, trace, warn};
 
 use arc_swap::ArcSwapOption;
-use async_trait::async_trait;
 
 use serde::{Deserialize, Serialize};
 use sodiumoxide::crypto::auth;
@@ -457,7 +456,6 @@ impl NetApp {
 	}
 }
 
-#[async_trait]
 impl EndpointHandler<HelloMessage> for NetApp {
 	async fn handle(self: &Arc<Self>, msg: &HelloMessage, from: NodeID) {
 		debug!("Hello from {:?}: {:?}", hex::encode(&from[..8]), msg);
diff --git a/src/net/peering.rs b/src/net/peering.rs
index a8d271ec..08378a08 100644
--- a/src/net/peering.rs
+++ b/src/net/peering.rs
@@ -5,7 +5,6 @@ use std::sync::{Arc, RwLock};
 use std::time::{Duration, Instant};
 
 use arc_swap::ArcSwap;
-use async_trait::async_trait;
 use log::{debug, info, trace, warn};
 use serde::{Deserialize, Serialize};
 
@@ -592,7 +591,6 @@ impl PeeringManager {
 	}
 }
 
-#[async_trait]
 impl EndpointHandler<PingMessage> for PeeringManager {
 	async fn handle(self: &Arc<Self>, ping: &PingMessage, from: NodeID) -> PingMessage {
 		let ping_resp = PingMessage {
@@ -604,7 +602,6 @@ impl EndpointHandler<PingMessage> for PeeringManager {
 	}
 }
 
-#[async_trait]
 impl EndpointHandler<PeerListMessage> for PeeringManager {
 	async fn handle(
 		self: &Arc<Self>,
diff --git a/src/net/recv.rs b/src/net/recv.rs
index 0de7bef2..35a6d71a 100644
--- a/src/net/recv.rs
+++ b/src/net/recv.rs
@@ -1,7 +1,6 @@
 use std::collections::HashMap;
 use std::sync::Arc;
 
-use async_trait::async_trait;
 use bytes::Bytes;
 use log::*;
 
@@ -50,7 +49,6 @@ impl Drop for Sender {
 /// according to the protocol defined above: chunks of message in progress of being
 /// received are stored in a buffer, and when the last chunk of a message is received,
 /// the full message is passed to the receive handler.
-#[async_trait]
 pub(crate) trait RecvLoop: Sync + 'static {
 	fn recv_handler(self: &Arc<Self>, id: RequestID, stream: ByteStream);
 	fn cancel_handler(self: &Arc<Self>, _id: RequestID) {}
diff --git a/src/net/send.rs b/src/net/send.rs
index 1454eeb7..6f1ac02c 100644
--- a/src/net/send.rs
+++ b/src/net/send.rs
@@ -3,7 +3,6 @@ use std::pin::Pin;
 use std::sync::Arc;
 use std::task::{Context, Poll};
 
-use async_trait::async_trait;
 use bytes::{BufMut, Bytes, BytesMut};
 use log::*;
 
@@ -273,7 +272,6 @@ impl DataFrame {
 ///
 /// The `.send_loop()` exits when the sending end of the channel is closed,
 /// or if there is an error at any time writing to the async writer.
-#[async_trait]
 pub(crate) trait SendLoop: Sync {
 	async fn send_loop<W>(
 		self: Arc<Self>,
diff --git a/src/net/server.rs b/src/net/server.rs
index 36dccb2f..fb6c6366 100644
--- a/src/net/server.rs
+++ b/src/net/server.rs
@@ -3,7 +3,6 @@ use std::net::SocketAddr;
 use std::sync::{Arc, Mutex};
 
 use arc_swap::ArcSwapOption;
-use async_trait::async_trait;
 use log::*;
 
 use futures::io::{AsyncReadExt, AsyncWriteExt};
@@ -174,7 +173,6 @@ impl ServerConn {
 
 impl SendLoop for ServerConn {}
 
-#[async_trait]
 impl RecvLoop for ServerConn {
 	fn recv_handler(self: &Arc<Self>, id: RequestID, stream: ByteStream) {
 		let resp_send = match self.resp_send.load_full() {
diff --git a/src/rpc/system.rs b/src/rpc/system.rs
index 0fa68218..2a52ae5d 100644
--- a/src/rpc/system.rs
+++ b/src/rpc/system.rs
@@ -7,7 +7,6 @@ use std::sync::{Arc, RwLock, RwLockReadGuard};
 use std::time::{Duration, Instant};
 
 use arc_swap::ArcSwapOption;
-use async_trait::async_trait;
 use futures::join;
 use serde::{Deserialize, Serialize};
 use sodiumoxide::crypto::sign::ed25519;
@@ -749,7 +748,6 @@ impl System {
 	}
 }
 
-#[async_trait]
 impl EndpointHandler<SystemRpc> for System {
 	async fn handle(self: &Arc<Self>, msg: &SystemRpc, from: NodeID) -> Result<SystemRpc, Error> {
 		match msg {
diff --git a/src/table/gc.rs b/src/table/gc.rs
index 9e060390..28ea119d 100644
--- a/src/table/gc.rs
+++ b/src/table/gc.rs
@@ -4,6 +4,7 @@ use std::sync::Arc;
 use std::time::Duration;
 
 use async_trait::async_trait;
+
 use serde::{Deserialize, Serialize};
 use serde_bytes::ByteBuf;
 
@@ -272,7 +273,6 @@ impl<F: TableSchema, R: TableReplication> TableGc<F, R> {
 	}
 }
 
-#[async_trait]
 impl<F: TableSchema, R: TableReplication> EndpointHandler<GcRpc> for TableGc<F, R> {
 	async fn handle(self: &Arc<Self>, message: &GcRpc, _from: NodeID) -> Result<GcRpc, Error> {
 		match message {
diff --git a/src/table/sync.rs b/src/table/sync.rs
index 234ee8ea..2d43b9fc 100644
--- a/src/table/sync.rs
+++ b/src/table/sync.rs
@@ -444,7 +444,6 @@ impl<F: TableSchema, R: TableReplication> TableSyncer<F, R> {
 
 // ======= SYNCHRONIZATION PROCEDURE -- RECEIVER SIDE ======
 
-#[async_trait]
 impl<F: TableSchema, R: TableReplication> EndpointHandler<SyncRpc> for TableSyncer<F, R> {
 	async fn handle(self: &Arc<Self>, message: &SyncRpc, from: NodeID) -> Result<SyncRpc, Error> {
 		match message {
diff --git a/src/table/table.rs b/src/table/table.rs
index 255947e7..c96f4731 100644
--- a/src/table/table.rs
+++ b/src/table/table.rs
@@ -2,7 +2,6 @@ use std::borrow::Borrow;
 use std::collections::{BTreeMap, BTreeSet, HashMap};
 use std::sync::Arc;
 
-use async_trait::async_trait;
 use futures::stream::*;
 use serde::{Deserialize, Serialize};
 use serde_bytes::ByteBuf;
@@ -500,7 +499,6 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 	}
 }
 
-#[async_trait]
 impl<F: TableSchema, R: TableReplication> EndpointHandler<TableRpc<F>> for Table<F, R> {
 	async fn handle(
 		self: &Arc<Self>,