From fb8c11f25cb6ff4abc305d988a609751726e674e Mon Sep 17 00:00:00 2001
From: gatopeich <gatoguan-os@yahoo.com>
Date: Tue, 23 Jun 2020 15:01:20 +0100
Subject: [PATCH] Re-implement ordered_map::erase, so that it can handle
 pair<const Key,...>

---
 include/nlohmann/json.hpp        |  6 +++---
 include/nlohmann/ordered_map.hpp |  9 ++++++++-
 single_include/nlohmann/json.hpp | 15 +++++++++++----
 3 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/include/nlohmann/json.hpp b/include/nlohmann/json.hpp
index 31944e32..2aef23b3 100644
--- a/include/nlohmann/json.hpp
+++ b/include/nlohmann/json.hpp
@@ -499,9 +499,9 @@ class basic_json
           // Note the use of std::map default allocator as a placeholder
           // to extract the actual ObjectType::value_type
           AllocatorType<typename
-            ObjectType<StringType,basic_json,object_comparator_t,
-                std::allocator<std::pair<const StringType, basic_json>>
-                    >::value_type>>;
+          ObjectType<StringType, basic_json, object_comparator_t,
+          std::allocator<std::pair<const StringType, basic_json>>
+          >::value_type>>;
 
     /*!
     @brief a type for an array
diff --git a/include/nlohmann/ordered_map.hpp b/include/nlohmann/ordered_map.hpp
index 756b586a..bb5dfe4e 100644
--- a/include/nlohmann/ordered_map.hpp
+++ b/include/nlohmann/ordered_map.hpp
@@ -46,7 +46,14 @@ struct ordered_map : Container
         {
             if (it->first == key)
             {
-                Container::erase(it);
+                // Since we cannot move const Keys, re-construct them in place
+                for (auto next = it; ++next != this->end(); ++it)
+                {
+                    // *it = std::move(*next); // deleted
+                    it->~value_type(); // Destroy but keep allocation
+                    new (&*it) value_type{std::move(*next)};
+                }
+                Container::pop_back();
                 return 1;
             }
         }
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index 76ee2764..3cf133d5 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -15915,7 +15915,14 @@ struct ordered_map : Container
         {
             if (it->first == key)
             {
-                Container::erase(it);
+                // Since we cannot move const Keys, re-construct them in place
+                for (auto next = it; ++next != this->end(); ++it)
+                {
+                    // *it = std::move(*next); // deleted
+                    it->~value_type(); // Destroy but keep allocation
+                    new (&*it) value_type{std::move(*next)};
+                }
+                Container::pop_back();
                 return 1;
             }
         }
@@ -16351,9 +16358,9 @@ class basic_json
           // Note the use of std::map default allocator as a placeholder
           // to extract the actual ObjectType::value_type
           AllocatorType<typename
-            ObjectType<StringType,basic_json,object_comparator_t,
-                std::allocator<std::pair<const StringType, basic_json>>
-                    >::value_type>>;
+          ObjectType<StringType, basic_json, object_comparator_t,
+          std::allocator<std::pair<const StringType, basic_json>>
+          >::value_type>>;
 
     /*!
     @brief a type for an array