chore: remove Option<()> impl

actix-web/CHANGES.md

@@ -3,9 +3,9 @@
 ## Unreleased
 
 - On Windows, an error is now returned from `HttpServer::bind()` (or TLS variants) when binding to a socket that's already in use.
+- Implemented `Responder` for `Result<(), E: Into<Error>>`. Returning `Ok(())` responds with HTTP 204 No Content.
 - Update `brotli` dependency to `7`.
 - Minimum supported Rust version (MSRV) is now 1.75.
-- Implemented responder for `Option<()>` and `Result<(), E: Error> to respond with `204 No Content`
 
 ## 4.9.0
 

actix-web/src/response/responder.rs

@@ -116,17 +116,6 @@ impl<R: Responder> Responder for Option<R> {
     }
 }
 
-//Note see https://github.com/actix/actix-web/issues/1108 on why Responder is not implemented for ()
-impl Responder for Option<()> {
-    type Body = BoxBody;
-    fn respond_to(self, _req: &HttpRequest) -> HttpResponse {
-        match self {
-            Some(()) => HttpResponse::NoContent().finish(),
-            None => HttpResponse::NotFound().finish(),
-        }
-    }
-}
-
 impl<R, E> Responder for Result<R, E>
 where
     R: Responder,
@@ -142,14 +131,19 @@ where
     }
 }
 
-//Note see https://github.com/actix/actix-web/issues/1108 on why Responder is not implemented for ()
+// Note: see https://github.com/actix/actix-web/issues/1108 for reasoning why Responder is not
-impl<E: Into<Error>> Responder for Result<(), E> {
+// implemented for `()`, and https://github.com/actix/actix-web/pull/3560 for discussion about this
+// impl and the decision not to include a similar one for `Option<()>`.
+impl<E> Responder for Result<(), E>
+where
+    E: Into<Error>,
+{
     type Body = BoxBody;
 
     fn respond_to(self, _req: &HttpRequest) -> HttpResponse {
         match self {
             Ok(()) => HttpResponse::new(StatusCode::NO_CONTENT),
-            Err(e) => HttpResponse::from_error(e.into()),
+            Err(err) => HttpResponse::from_error(err.into()),
         }
     }
 }