diff --git a/include/boost/unordered/concurrent_flat_map.hpp b/include/boost/unordered/concurrent_flat_map.hpp
index 07b6ea7b..4ec1ea27 100644
--- a/include/boost/unordered/concurrent_flat_map.hpp
+++ b/include/boost/unordered/concurrent_flat_map.hpp
@@ -772,10 +772,10 @@ namespace boost {
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
       class Allocator = std::allocator<
         boost::unordered::detail::iter_to_alloc_t<InputIterator> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_map(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -788,9 +788,9 @@ namespace boost {
       class Hash = boost::hash<std::remove_const_t<Key> >,
       class Pred = std::equal_to<std::remove_const_t<Key> >,
       class Allocator = std::allocator<std::pair<const Key, T> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_map(std::initializer_list<std::pair<Key, T> >,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -798,8 +798,8 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_map(InputIterator, InputIterator, std::size_t, Allocator)
       -> concurrent_flat_map<
         boost::unordered::detail::iter_key_t<InputIterator>,
@@ -809,8 +809,8 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_map(InputIterator, InputIterator, Allocator)
       -> concurrent_flat_map<
         boost::unordered::detail::iter_key_t<InputIterator>,
@@ -820,9 +820,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_map(
       InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> concurrent_flat_map<
@@ -832,22 +832,22 @@ namespace boost {
         Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_map(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Allocator) -> concurrent_flat_map<std::remove_const_t<Key>, T,
       boost::hash<std::remove_const_t<Key> >,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_map(std::initializer_list<std::pair<Key, T> >, Allocator)
       -> concurrent_flat_map<std::remove_const_t<Key>, T,
         boost::hash<std::remove_const_t<Key> >,
         std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_map(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Hash, Allocator) -> concurrent_flat_map<std::remove_const_t<Key>, T,
       Hash, std::equal_to<std::remove_const_t<Key> >, Allocator>;
diff --git a/include/boost/unordered/concurrent_flat_set.hpp b/include/boost/unordered/concurrent_flat_set.hpp
index c55a9681..f86c6b91 100644
--- a/include/boost/unordered/concurrent_flat_set.hpp
+++ b/include/boost/unordered/concurrent_flat_set.hpp
@@ -640,10 +640,10 @@ namespace boost {
         std::equal_to<typename std::iterator_traits<InputIterator>::value_type>,
       class Allocator = std::allocator<
         typename std::iterator_traits<InputIterator>::value_type>,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_set(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -653,17 +653,17 @@ namespace boost {
 
     template <class T, class Hash = boost::hash<T>,
       class Pred = std::equal_to<T>, class Allocator = std::allocator<T>,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_set(std::initializer_list<T>,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> concurrent_flat_set< T, Hash, Pred, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_set(InputIterator, InputIterator, std::size_t, Allocator)
       -> concurrent_flat_set<
         typename std::iterator_traits<InputIterator>::value_type,
@@ -672,8 +672,8 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_set(InputIterator, InputIterator, Allocator)
       -> concurrent_flat_set<
         typename std::iterator_traits<InputIterator>::value_type,
@@ -682,9 +682,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_set(
       InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> concurrent_flat_set<
@@ -693,18 +693,18 @@ namespace boost {
         Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_set(std::initializer_list<T>, std::size_t, Allocator)
       -> concurrent_flat_set<T, boost::hash<T>,std::equal_to<T>, Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_set(std::initializer_list<T >, Allocator)
       -> concurrent_flat_set<T, boost::hash<T>, std::equal_to<T>, Allocator>;
 
     template <class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     concurrent_flat_set(std::initializer_list<T >, std::size_t,Hash, Allocator)
       -> concurrent_flat_set<T, Hash, std::equal_to<T>, Allocator>;
 
diff --git a/include/boost/unordered/unordered_flat_map.hpp b/include/boost/unordered/unordered_flat_map.hpp
index d70064a8..5d565a31 100644
--- a/include/boost/unordered/unordered_flat_map.hpp
+++ b/include/boost/unordered/unordered_flat_map.hpp
@@ -717,10 +717,10 @@ namespace boost {
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
       class Allocator = std::allocator<
         boost::unordered::detail::iter_to_alloc_t<InputIterator> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_map(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -732,9 +732,9 @@ namespace boost {
       class Hash = boost::hash<std::remove_const_t<Key> >,
       class Pred = std::equal_to<std::remove_const_t<Key> >,
       class Allocator = std::allocator<std::pair<const Key, T> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_map(std::initializer_list<std::pair<Key, T> >,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -742,8 +742,8 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_map(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_flat_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
@@ -752,8 +752,8 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_map(InputIterator, InputIterator, Allocator)
       -> unordered_flat_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
@@ -762,9 +762,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_map(
       InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_flat_map<boost::unordered::detail::iter_key_t<InputIterator>,
@@ -773,22 +773,22 @@ namespace boost {
         Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_map(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Allocator) -> unordered_flat_map<std::remove_const_t<Key>, T,
       boost::hash<std::remove_const_t<Key> >,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_map(std::initializer_list<std::pair<Key, T> >, Allocator)
       -> unordered_flat_map<std::remove_const_t<Key>, T,
         boost::hash<std::remove_const_t<Key> >,
         std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_map(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Hash, Allocator) -> unordered_flat_map<std::remove_const_t<Key>, T,
       Hash, std::equal_to<std::remove_const_t<Key> >, Allocator>;
diff --git a/include/boost/unordered/unordered_flat_set.hpp b/include/boost/unordered/unordered_flat_set.hpp
index 3198dcee..a6aba397 100644
--- a/include/boost/unordered/unordered_flat_set.hpp
+++ b/include/boost/unordered/unordered_flat_set.hpp
@@ -535,10 +535,10 @@ namespace boost {
         std::equal_to<typename std::iterator_traits<InputIterator>::value_type>,
       class Allocator = std::allocator<
         typename std::iterator_traits<InputIterator>::value_type>,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_set(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -548,17 +548,17 @@ namespace boost {
 
     template <class T, class Hash = boost::hash<T>,
       class Pred = std::equal_to<T>, class Allocator = std::allocator<T>,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_set(std::initializer_list<T>,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_flat_set<T, Hash, Pred, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_set(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_flat_set<
         typename std::iterator_traits<InputIterator>::value_type,
@@ -567,9 +567,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_set(
       InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_flat_set<
@@ -578,19 +578,19 @@ namespace boost {
         Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_set(std::initializer_list<T>, std::size_t, Allocator)
       -> unordered_flat_set<T, boost::hash<T>, std::equal_to<T>, Allocator>;
 
     template <class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_set(std::initializer_list<T>, std::size_t, Hash, Allocator)
       -> unordered_flat_set<T, Hash, std::equal_to<T>, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_set(InputIterator, InputIterator, Allocator)
       -> unordered_flat_set<
         typename std::iterator_traits<InputIterator>::value_type,
@@ -599,7 +599,7 @@ namespace boost {
         Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_flat_set(std::initializer_list<T>, Allocator)
       -> unordered_flat_set<T, boost::hash<T>, std::equal_to<T>, Allocator>;
 #endif
diff --git a/include/boost/unordered/unordered_map.hpp b/include/boost/unordered/unordered_map.hpp
index fa12a749..ba10a970 100644
--- a/include/boost/unordered/unordered_map.hpp
+++ b/include/boost/unordered/unordered_map.hpp
@@ -605,10 +605,10 @@ namespace boost {
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
       class Allocator = std::allocator<
         boost::unordered::detail::iter_to_alloc_t<InputIterator> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -620,17 +620,17 @@ namespace boost {
       class Hash = boost::hash<std::remove_const_t<Key> >,
       class Pred = std::equal_to<std::remove_const_t<Key> >,
       class Allocator = std::allocator<std::pair<const Key, T> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(std::initializer_list<std::pair<Key, T> >,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_map<std::remove_const_t<Key>, T, Hash, Pred, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
@@ -639,8 +639,8 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(InputIterator, InputIterator, Allocator)
       -> unordered_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
@@ -649,9 +649,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>, Hash,
@@ -659,22 +659,22 @@ namespace boost {
         Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Allocator) -> unordered_map<std::remove_const_t<Key>, T,
       boost::hash<std::remove_const_t<Key> >,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(std::initializer_list<std::pair<Key, T> >, Allocator)
       -> unordered_map<std::remove_const_t<Key>, T,
         boost::hash<std::remove_const_t<Key> >,
         std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_map(std::initializer_list<std::pair<Key, T> >, std::size_t, Hash,
       Allocator) -> unordered_map<std::remove_const_t<Key>, T, Hash,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
@@ -1124,10 +1124,10 @@ namespace boost {
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
       class Allocator = std::allocator<
         boost::unordered::detail::iter_to_alloc_t<InputIterator> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -1139,17 +1139,17 @@ namespace boost {
       class Hash = boost::hash<std::remove_const_t<Key> >,
       class Pred = std::equal_to<std::remove_const_t<Key> >,
       class Allocator = std::allocator<std::pair<const Key, T> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(std::initializer_list<std::pair<Key, T> >,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_multimap<std::remove_const_t<Key>, T, Hash, Pred, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_multimap<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
@@ -1158,8 +1158,8 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(InputIterator, InputIterator, Allocator)
       -> unordered_multimap<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
@@ -1168,9 +1168,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(
       InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_multimap<boost::unordered::detail::iter_key_t<InputIterator>,
@@ -1179,22 +1179,22 @@ namespace boost {
         Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Allocator) -> unordered_multimap<std::remove_const_t<Key>, T,
       boost::hash<std::remove_const_t<Key> >,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(std::initializer_list<std::pair<Key, T> >, Allocator)
       -> unordered_multimap<std::remove_const_t<Key>, T,
         boost::hash<std::remove_const_t<Key> >,
         std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multimap(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Hash, Allocator) -> unordered_multimap<std::remove_const_t<Key>, T, Hash,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
diff --git a/include/boost/unordered/unordered_node_map.hpp b/include/boost/unordered/unordered_node_map.hpp
index 51f2e0eb..d2ea4bf8 100644
--- a/include/boost/unordered/unordered_node_map.hpp
+++ b/include/boost/unordered/unordered_node_map.hpp
@@ -810,10 +810,10 @@ namespace boost {
         std::equal_to<boost::unordered::detail::iter_key_t<InputIterator> >,
       class Allocator = std::allocator<
         boost::unordered::detail::iter_to_alloc_t<InputIterator> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_map(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -825,9 +825,9 @@ namespace boost {
       class Hash = boost::hash<std::remove_const_t<Key> >,
       class Pred = std::equal_to<std::remove_const_t<Key> >,
       class Allocator = std::allocator<std::pair<const Key, T> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_map(std::initializer_list<std::pair<Key, T> >,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -835,8 +835,8 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_map(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_node_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
@@ -845,8 +845,8 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_map(InputIterator, InputIterator, Allocator)
       -> unordered_node_map<boost::unordered::detail::iter_key_t<InputIterator>,
         boost::unordered::detail::iter_val_t<InputIterator>,
@@ -855,9 +855,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_map(
       InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_node_map<boost::unordered::detail::iter_key_t<InputIterator>,
@@ -866,22 +866,22 @@ namespace boost {
         Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_map(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Allocator) -> unordered_node_map<std::remove_const_t<Key>, T,
       boost::hash<std::remove_const_t<Key> >,
       std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_map(std::initializer_list<std::pair<Key, T> >, Allocator)
       -> unordered_node_map<std::remove_const_t<Key>, T,
         boost::hash<std::remove_const_t<Key> >,
         std::equal_to<std::remove_const_t<Key> >, Allocator>;
 
     template <class Key, class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_map(std::initializer_list<std::pair<Key, T> >, std::size_t,
       Hash, Allocator) -> unordered_node_map<std::remove_const_t<Key>, T,
       Hash, std::equal_to<std::remove_const_t<Key> >, Allocator>;
diff --git a/include/boost/unordered/unordered_node_set.hpp b/include/boost/unordered/unordered_node_set.hpp
index aa244f50..9012609b 100644
--- a/include/boost/unordered/unordered_node_set.hpp
+++ b/include/boost/unordered/unordered_node_set.hpp
@@ -622,10 +622,10 @@ namespace boost {
         std::equal_to<typename std::iterator_traits<InputIterator>::value_type>,
       class Allocator = std::allocator<
         typename std::iterator_traits<InputIterator>::value_type>,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_set(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -635,17 +635,17 @@ namespace boost {
 
     template <class T, class Hash = boost::hash<T>,
       class Pred = std::equal_to<T>, class Allocator = std::allocator<T>,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_set(std::initializer_list<T>,
       std::size_t = boost::unordered::detail::foa::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_node_set<T, Hash, Pred, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_set(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_node_set<
         typename std::iterator_traits<InputIterator>::value_type,
@@ -654,9 +654,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_set(
       InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_node_set<
@@ -665,19 +665,19 @@ namespace boost {
         Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_set(std::initializer_list<T>, std::size_t, Allocator)
       -> unordered_node_set<T, boost::hash<T>, std::equal_to<T>, Allocator>;
 
     template <class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_set(std::initializer_list<T>, std::size_t, Hash, Allocator)
       -> unordered_node_set<T, Hash, std::equal_to<T>, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_set(InputIterator, InputIterator, Allocator)
       -> unordered_node_set<
         typename std::iterator_traits<InputIterator>::value_type,
@@ -686,7 +686,7 @@ namespace boost {
         Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_node_set(std::initializer_list<T>, Allocator)
       -> unordered_node_set<T, boost::hash<T>, std::equal_to<T>, Allocator>;
 #endif
diff --git a/include/boost/unordered/unordered_set.hpp b/include/boost/unordered/unordered_set.hpp
index eb375c57..680b6565 100644
--- a/include/boost/unordered/unordered_set.hpp
+++ b/include/boost/unordered/unordered_set.hpp
@@ -462,10 +462,10 @@ namespace boost {
         std::equal_to<typename std::iterator_traits<InputIterator>::value_type>,
       class Allocator = std::allocator<
         typename std::iterator_traits<InputIterator>::value_type>,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_set(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -474,17 +474,17 @@ namespace boost {
 
     template <class T, class Hash = boost::hash<T>,
       class Pred = std::equal_to<T>, class Allocator = std::allocator<T>,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_set(std::initializer_list<T>,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_set<T, Hash, Pred, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_set(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_set<typename std::iterator_traits<InputIterator>::value_type,
         boost::hash<typename std::iterator_traits<InputIterator>::value_type>,
@@ -492,9 +492,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_set(InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_set<typename std::iterator_traits<InputIterator>::value_type,
         Hash,
@@ -502,19 +502,19 @@ namespace boost {
         Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_set(std::initializer_list<T>, std::size_t, Allocator)
       -> unordered_set<T, boost::hash<T>, std::equal_to<T>, Allocator>;
 
     template <class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_set(std::initializer_list<T>, std::size_t, Hash, Allocator)
       -> unordered_set<T, Hash, std::equal_to<T>, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_set(InputIterator, InputIterator, Allocator)
       -> unordered_set<typename std::iterator_traits<InputIterator>::value_type,
         boost::hash<typename std::iterator_traits<InputIterator>::value_type>,
@@ -522,7 +522,7 @@ namespace boost {
         Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_set(std::initializer_list<T>, Allocator)
       -> unordered_set<T, boost::hash<T>, std::equal_to<T>, Allocator>;
 
@@ -925,10 +925,10 @@ namespace boost {
         std::equal_to<typename std::iterator_traits<InputIterator>::value_type>,
       class Allocator = std::allocator<
         typename std::iterator_traits<InputIterator>::value_type>,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multiset(InputIterator, InputIterator,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
@@ -938,17 +938,17 @@ namespace boost {
 
     template <class T, class Hash = boost::hash<T>,
       class Pred = std::equal_to<T>, class Allocator = std::allocator<T>,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_pred_v<Pred> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_pred_v<Pred> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multiset(std::initializer_list<T>,
       std::size_t = boost::unordered::detail::default_bucket_count,
       Hash = Hash(), Pred = Pred(), Allocator = Allocator())
       -> unordered_multiset<T, Hash, Pred, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multiset(InputIterator, InputIterator, std::size_t, Allocator)
       -> unordered_multiset<
         typename std::iterator_traits<InputIterator>::value_type,
@@ -957,9 +957,9 @@ namespace boost {
         Allocator>;
 
     template <class InputIterator, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multiset(
       InputIterator, InputIterator, std::size_t, Hash, Allocator)
       -> unordered_multiset<
@@ -968,19 +968,19 @@ namespace boost {
         Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multiset(std::initializer_list<T>, std::size_t, Allocator)
       -> unordered_multiset<T, boost::hash<T>, std::equal_to<T>, Allocator>;
 
     template <class T, class Hash, class Allocator,
-      class = boost::enable_if_t<detail::is_hash_v<Hash> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_hash_v<Hash> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multiset(std::initializer_list<T>, std::size_t, Hash, Allocator)
       -> unordered_multiset<T, Hash, std::equal_to<T>, Allocator>;
 
     template <class InputIterator, class Allocator,
-      class = boost::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_input_iterator_v<InputIterator> >,
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multiset(InputIterator, InputIterator, Allocator)
       -> unordered_multiset<
         typename std::iterator_traits<InputIterator>::value_type,
@@ -989,7 +989,7 @@ namespace boost {
         Allocator>;
 
     template <class T, class Allocator,
-      class = boost::enable_if_t<detail::is_allocator_v<Allocator> > >
+      class = std::enable_if_t<detail::is_allocator_v<Allocator> > >
     unordered_multiset(std::initializer_list<T>, Allocator)
       -> unordered_multiset<T, boost::hash<T>, std::equal_to<T>, Allocator>;