From 958d360ac4c93df6bae4c23704d5b4418fe1d448 Mon Sep 17 00:00:00 2001
From: David Pedersen <david.pdrsn@gmail.com>
Date: Thu, 20 Oct 2022 21:05:04 +0200
Subject: [PATCH] Generalize `AppendHeaders` to accept any `impl IntoIterator`
 (#1495)

* Generalize `AppendHeaders` to accept any `impl IntoIterator`

* changelog
---
 axum-core/CHANGELOG.md                   | 2 ++
 axum-core/src/response/append_headers.rs | 8 +++++---
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/axum-core/CHANGELOG.md b/axum-core/CHANGELOG.md
index 84673d69..1a64d889 100644
--- a/axum-core/CHANGELOG.md
+++ b/axum-core/CHANGELOG.md
@@ -9,9 +9,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - **added:** Add `DefaultBodyLimit::max` for changing the default body limit ([#1397])
 - **added:** Add `Error::into_inner` for converting `Error` to `BoxError` without allocating ([#1476])
+- **breaking:** `AppendHeaders` now works on any `impl IntoIterator` ([#1495])
 
 [#1397]: https://github.com/tokio-rs/axum/pull/1397
 [#1476]: https://github.com/tokio-rs/axum/pull/1476
+[#1495]: https://github.com/tokio-rs/axum/pull/1495
 
 # 0.3.0-rc.2 (10. September, 2022)
 
diff --git a/axum-core/src/response/append_headers.rs b/axum-core/src/response/append_headers.rs
index d777332f..4f1ae964 100644
--- a/axum-core/src/response/append_headers.rs
+++ b/axum-core/src/response/append_headers.rs
@@ -30,10 +30,11 @@ use std::fmt;
 /// }
 /// ```
 #[derive(Debug)]
-pub struct AppendHeaders<K, V, const N: usize>(pub [(K, V); N]);
+pub struct AppendHeaders<I>(pub I);
 
-impl<K, V, const N: usize> IntoResponse for AppendHeaders<K, V, N>
+impl<I, K, V> IntoResponse for AppendHeaders<I>
 where
+    I: IntoIterator<Item = (K, V)>,
     K: TryInto<HeaderName>,
     K::Error: fmt::Display,
     V: TryInto<HeaderValue>,
@@ -44,8 +45,9 @@ where
     }
 }
 
-impl<K, V, const N: usize> IntoResponseParts for AppendHeaders<K, V, N>
+impl<I, K, V> IntoResponseParts for AppendHeaders<I>
 where
+    I: IntoIterator<Item = (K, V)>,
     K: TryInto<HeaderName>,
     K::Error: fmt::Display,
     V: TryInto<HeaderValue>,