Use derive_more to derive AsRef.

Cargo.lock

@@ -3399,6 +3399,7 @@ name = "tor-guardmgr"
 version = "0.1.0"
 dependencies = [
  "derive_builder",
+ "derive_more",
  "educe",
  "futures",
  "humantime-serde",

crates/tor-guardmgr/Cargo.toml

@@ -30,6 +30,7 @@ tor-rtcompat = { path = "../tor-rtcompat", version = "0.1.0" }
 tor-units = { path = "../tor-units", version = "0.1.0" }
 
 derive_builder = "0.11"
+derive_more = "0.99"
 educe = "0.4.6"
 futures = "0.3.14"
 humantime-serde = "1.1.1"

crates/tor-guardmgr/src/ids.rs

@@ -1,5 +1,6 @@
 //! Identifier objects used to specify guards and/or fallbacks.
 
+use derive_more::AsRef;
 use serde::{Deserialize, Serialize};
 use tor_llcrypto::pk;
 
@@ -16,7 +17,7 @@ pub(crate) struct IdPair {
 ///
 /// This is a separate type from GuardId and FirstHopId to avoid confusion
 /// about what kind of object we're identifying.
-#[derive(Clone, Debug, Eq, PartialEq, Hash, Ord, PartialOrd)]
+#[derive(Clone, Debug, Eq, PartialEq, Hash, Ord, PartialOrd, AsRef)]
 pub(crate) struct FallbackId(pub(crate) IdPair);
 
 impl FallbackId {
@@ -29,17 +30,12 @@ impl FallbackId {
         Self::new(*target.ed_identity(), *target.rsa_identity())
     }
 }
-impl AsRef<IdPair> for FallbackId {
-    fn as_ref(&self) -> &IdPair {
-        &self.0
-    }
-}
 
 /// An identifier for a sampled guard.
 ///
 /// This is a separate type from GuardId and FirstHopId to avoid confusion
 /// about what kind of object we're identifying.
-#[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialEq, Hash, Ord, PartialOrd)]
+#[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialEq, Hash, Ord, PartialOrd, AsRef)]
 #[serde(transparent)]
 pub(crate) struct GuardId(pub(crate) IdPair);
 
@@ -53,11 +49,6 @@ impl GuardId {
         Self::new(*target.ed_identity(), *target.rsa_identity())
     }
 }
-impl AsRef<IdPair> for GuardId {
-    fn as_ref(&self) -> &IdPair {
-        &self.0
-    }
-}
 
 /// Implementation type held inside of FirstHopId.
 ///