Remove deprecated features to allow compiling with C++17 compilers fixes

 #592

changelog.md

@@ -35,6 +35,10 @@ HEAD
   #599 Thank you Gianfranco Costamagna for reporting.
 - Compatibility: Add missing `<stdint>` headers. Fixes issues with g++ 5.4.0.
   #638 Thank you Alex Korotkin for reporting and a patch.
+- Compatibility: Remove the use of `std::auto_ptr` and `std::binary_function`
+  from builds with C++11 or later. These features are deprecated and were
+  removed entirely in C++17. This change allows building WebSocket++ on
+  C++17 compilers. #592 Thank you Michal Fojtak for reporting and a patch
 - Bug: Store loggers in shared pointers to avoid crashes related to connections
   trying to write logs entries after their respective endpoint has been
   deallocated. Thank you Thalhammer for reporting and Jupp Müller for the 

websocketpp/common/memory.hpp

@@ -65,7 +65,6 @@ namespace lib {
 #ifdef _WEBSOCKETPP_CPP11_MEMORY_
     using std::shared_ptr;
     using std::weak_ptr;
-    using std::auto_ptr;
     using std::enable_shared_from_this;
     using std::static_pointer_cast;
     using std::make_shared;

websocketpp/utilities.hpp

@@ -72,11 +72,9 @@ struct my_equal {
  * Based on code from
  * http://stackoverflow.com/questions/3152241/case-insensitive-stdstring-find
  */
-struct ci_less : std::binary_function<std::string, std::string, bool> {
+struct ci_less {
     // case-independent (ci) compare_less binary function
-    struct nocase_compare
-      : public std::binary_function<unsigned char,unsigned char,bool>
-    {
+    struct nocase_compare {
         bool operator() (unsigned char const & c1, unsigned char const & c2) const {
             return tolower (c1) < tolower (c2);
         }