From 4a9ba2088c487b2bde2768b8cdc00a73e3eb72a8 Mon Sep 17 00:00:00 2001
From: An Tao <antao2002@gmail.com>
Date: Wed, 26 Aug 2020 20:53:04 +0800
Subject: [PATCH] Remove the expired std::iterator template (#554)

---
 orm_lib/inc/drogon/orm/ResultIterator.h | 9 ++-------
 orm_lib/inc/drogon/orm/RowIterator.h    | 8 ++------
 2 files changed, 4 insertions(+), 13 deletions(-)

diff --git a/orm_lib/inc/drogon/orm/ResultIterator.h b/orm_lib/inc/drogon/orm/ResultIterator.h
index 643ceb9d..d4f1eefd 100644
--- a/orm_lib/inc/drogon/orm/ResultIterator.h
+++ b/orm_lib/inc/drogon/orm/ResultIterator.h
@@ -23,15 +23,10 @@ namespace drogon
 {
 namespace orm
 {
-class ConstResultIterator
-    : public std::iterator<std::random_access_iterator_tag,
-                           const Row,
-                           Result::DifferenceType,
-                           ConstResultIterator,
-                           Row>,
-      protected Row
+class ConstResultIterator : protected Row
 {
   public:
+    using iterator_category = std::random_access_iterator_tag;
     using pointer = const Row *;
     using reference = const Row &;
     using value_type = const Row;
diff --git a/orm_lib/inc/drogon/orm/RowIterator.h b/orm_lib/inc/drogon/orm/RowIterator.h
index 5e2feb0e..3015aa07 100644
--- a/orm_lib/inc/drogon/orm/RowIterator.h
+++ b/orm_lib/inc/drogon/orm/RowIterator.h
@@ -23,12 +23,7 @@ namespace drogon
 {
 namespace orm
 {
-class ConstRowIterator : public std::iterator<std::random_access_iterator_tag,
-                                              const Field,
-                                              Row::DifferenceType,
-                                              ConstRowIterator,
-                                              Field>,
-                         protected Field
+class ConstRowIterator : protected Field
 {
   public:
     using pointer = const Field *;
@@ -36,6 +31,7 @@ class ConstRowIterator : public std::iterator<std::random_access_iterator_tag,
     using value_type = const Field;
     using size_type = Row::SizeType;
     using difference_type = Row::DifferenceType;
+    using iterator_category = std::random_access_iterator_tag;
     // ConstRowIterator(const Field &t) noexcept : Field(t) {}
 
     pointer operator->()