From 9e167ef60ac6201971867a74a6d00628fd7a0106 Mon Sep 17 00:00:00 2001
From: Steven Fackler <sfackler@gmail.com>
Date: Thu, 21 Apr 2016 22:19:49 -0700
Subject: [PATCH] Add Entry::key

This method was present on both variants of Entry, but not the enum

cc #32281
---
 src/libcollections/btree/map.rs    | 9 +++++++++
 src/libstd/collections/hash/map.rs | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/src/libcollections/btree/map.rs b/src/libcollections/btree/map.rs
index de40568fd67..0dbdad98c86 100644
--- a/src/libcollections/btree/map.rs
+++ b/src/libcollections/btree/map.rs
@@ -1522,6 +1522,15 @@ impl<'a, K: Ord, V> Entry<'a, K, V> {
             Vacant(entry) => entry.insert(default()),
         }
     }
+
+    /// Returns a reference to this entry's key.
+    #[unstable(feature = "map_entry_keys", issue = "32281")]
+    pub fn key(&self) -> &K {
+        match *self {
+            Occupied(ref entry) => entry.key(),
+            Vacant(ref entry) => entry.key(),
+        }
+    }
 }
 
 impl<'a, K: Ord, V> VacantEntry<'a, K, V> {
diff --git a/src/libstd/collections/hash/map.rs b/src/libstd/collections/hash/map.rs
index c20270e8306..4b5696b7913 100644
--- a/src/libstd/collections/hash/map.rs
+++ b/src/libstd/collections/hash/map.rs
@@ -1533,6 +1533,15 @@ impl<'a, K, V> Entry<'a, K, V> {
             Vacant(entry) => entry.insert(default()),
         }
     }
+
+    /// Returns a reference to this entry's key.
+    #[unstable(feature = "map_entry_keys", issue = "32281")]
+    pub fn key(&self) -> &K {
+        match *self {
+            Occupied(ref entry) => entry.key(),
+            Vacant(ref entry) => entry.key(),
+        }
+    }
 }
 
 impl<'a, K, V> OccupiedEntry<'a, K, V> {