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[PATCH] P0458R2 Checking for Existence of an Element in Associative Containers
- From: Jonathan Wakely <jwakely at redhat dot com>
- To: libstdc++ at gcc dot gnu dot org, gcc-patches at gcc dot gnu dot org
- Date: Wed, 4 Jul 2018 19:16:25 +0100
- Subject: [PATCH] P0458R2 Checking for Existence of an Element in Associative Containers
* include/bits/stl_map.h (map::contains): Add for C++2a.
* include/bits/stl_multimap.h (multimap::contains): Likewise.
* include/bits/stl_multiset.h (multiset::contains): Likewise.
* include/bits/stl_set.h (set::contains): Likewise.
* include/bits/stl_tree.h (__has_is_transparent_t): Define alias.
(_Rb_tree::_M_find_tr, _Rb_tree::_M_count_tr)
(_Rb_tree::_M_lower_bound_tr, _Rb_tree::_M_upper_bound_tr)
(_Rb_tree::_M_equal_range_tr): Use __has_is_transparent_t.
* include/bits/unordered_map.h (unordered_map::contains)
(unordered_multimap::contains): Add for C++2a.
* include/bits/unordered_set.h (unordered_set::contains)
(unordered_multiset::contains): Likewise.
* testsuite/23_containers/map/operations/contains.cc: New.
* testsuite/23_containers/multimap/operations/contains.cc: New.
* testsuite/23_containers/multiset/operations/contains.cc: New.
* testsuite/23_containers/set/operations/contains.cc: New.
* testsuite/23_containers/unordered_map/operations/contains.cc: New.
* testsuite/23_containers/unordered_multimap/operations/contains.cc:
New.
* testsuite/23_containers/unordered_multiset/operations/contains.cc:
New.
* testsuite/23_containers/unordered_set/operations/contains.cc: New.
Tested powerpc64le-linux, committed to trunk.
commit c38607c44696e07f44f56abf339f5453b04a5e70
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Wed Jul 4 19:15:11 2018 +0100
P0458R2 Checking for Existence of an Element in Associative Containers
* include/bits/stl_map.h (map::contains): Add for C++2a.
* include/bits/stl_multimap.h (multimap::contains): Likewise.
* include/bits/stl_multiset.h (multiset::contains): Likewise.
* include/bits/stl_set.h (set::contains): Likewise.
* include/bits/stl_tree.h (__has_is_transparent_t): Define alias.
(_Rb_tree::_M_find_tr, _Rb_tree::_M_count_tr)
(_Rb_tree::_M_lower_bound_tr, _Rb_tree::_M_upper_bound_tr)
(_Rb_tree::_M_equal_range_tr): Use __has_is_transparent_t.
* include/bits/unordered_map.h (unordered_map::contains)
(unordered_multimap::contains): Add for C++2a.
* include/bits/unordered_set.h (unordered_set::contains)
(unordered_multiset::contains): Likewise.
* testsuite/23_containers/map/operations/contains.cc: New.
* testsuite/23_containers/multimap/operations/contains.cc: New.
* testsuite/23_containers/multiset/operations/contains.cc: New.
* testsuite/23_containers/set/operations/contains.cc: New.
* testsuite/23_containers/unordered_map/operations/contains.cc: New.
* testsuite/23_containers/unordered_multimap/operations/contains.cc:
New.
* testsuite/23_containers/unordered_multiset/operations/contains.cc:
New.
* testsuite/23_containers/unordered_set/operations/contains.cc: New.
diff --git a/libstdc++-v3/include/bits/stl_map.h b/libstdc++-v3/include/bits/stl_map.h
index b81a2c4b7fc..fdd058b060d 100644
--- a/libstdc++-v3/include/bits/stl_map.h
+++ b/libstdc++-v3/include/bits/stl_map.h
@@ -1223,6 +1223,25 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
#endif
//@}
+#if __cplusplus > 201703L
+ //@{
+ /**
+ * @brief Finds whether an element with the given key exists.
+ * @param __x Key of (key, value) pairs to be located.
+ * @return True if there is an element with the specified key.
+ */
+ bool
+ contains(const key_type& __x) const
+ { return _M_t.find(__x) != _M_t.end(); }
+
+ template<typename _Kt>
+ auto
+ contains(const _Kt& __x) const
+ -> decltype(_M_t._M_find_tr(__x), void(), true)
+ { return _M_t._M_find_tr(__x) != _M_t.end(); }
+ //@}
+#endif
+
//@{
/**
* @brief Finds the beginning of a subsequence matching given key.
diff --git a/libstdc++-v3/include/bits/stl_multimap.h b/libstdc++-v3/include/bits/stl_multimap.h
index 23332ee53f8..9357d1db6aa 100644
--- a/libstdc++-v3/include/bits/stl_multimap.h
+++ b/libstdc++-v3/include/bits/stl_multimap.h
@@ -893,6 +893,25 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
#endif
//@}
+#if __cplusplus > 201703L
+ //@{
+ /**
+ * @brief Finds whether an element with the given key exists.
+ * @param __x Key of (key, value) pairs to be located.
+ * @return True if there is any element with the specified key.
+ */
+ bool
+ contains(const key_type& __x) const
+ { return _M_t.find(__x) != _M_t.end(); }
+
+ template<typename _Kt>
+ auto
+ contains(const _Kt& __x) const
+ -> decltype(_M_t._M_find_tr(__x), void(), true)
+ { return _M_t._M_find_tr(__x) != _M_t.end(); }
+ //@}
+#endif
+
//@{
/**
* @brief Finds the beginning of a subsequence matching given key.
diff --git a/libstdc++-v3/include/bits/stl_multiset.h b/libstdc++-v3/include/bits/stl_multiset.h
index 829bc96e8b2..ebac76731ed 100644
--- a/libstdc++-v3/include/bits/stl_multiset.h
+++ b/libstdc++-v3/include/bits/stl_multiset.h
@@ -738,6 +738,25 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
#endif
//@}
+#if __cplusplus > 201703L
+ //@{
+ /**
+ * @brief Finds whether an element with the given key exists.
+ * @param __x Key of elements to be located.
+ * @return True if there is any element with the specified key.
+ */
+ bool
+ contains(const key_type& __x) const
+ { return _M_t.find(__x) != _M_t.end(); }
+
+ template<typename _Kt>
+ auto
+ contains(const _Kt& __x) const
+ -> decltype(_M_t._M_find_tr(__x), void(), true)
+ { return _M_t._M_find_tr(__x) != _M_t.end(); }
+ //@}
+#endif
+
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 214. set::find() missing const overload
//@{
diff --git a/libstdc++-v3/include/bits/stl_set.h b/libstdc++-v3/include/bits/stl_set.h
index 41925265025..ee959d5fc1e 100644
--- a/libstdc++-v3/include/bits/stl_set.h
+++ b/libstdc++-v3/include/bits/stl_set.h
@@ -757,6 +757,25 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
#endif
//@}
+#if __cplusplus > 201703L
+ //@{
+ /**
+ * @brief Finds whether an element with the given key exists.
+ * @param __x Key of elements to be located.
+ * @return True if there is an element with the specified key.
+ */
+ bool
+ contains(const key_type& __x) const
+ { return _M_t.find(__x) != _M_t.end(); }
+
+ template<typename _Kt>
+ auto
+ contains(const _Kt& __x) const
+ -> decltype(_M_t._M_find_tr(__x), void(), true)
+ { return _M_t._M_find_tr(__x) != _M_t.end(); }
+ //@}
+#endif
+
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 214. set::find() missing const overload
//@{
diff --git a/libstdc++-v3/include/bits/stl_tree.h b/libstdc++-v3/include/bits/stl_tree.h
index 2403eba8eb3..0544f99f9ab 100644
--- a/libstdc++-v3/include/bits/stl_tree.h
+++ b/libstdc++-v3/include/bits/stl_tree.h
@@ -423,7 +423,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_Rb_tree_rebalance_for_erase(_Rb_tree_node_base* const __z,
_Rb_tree_node_base& __header) throw ();
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
template<typename _Cmp, typename _SfinaeType, typename = __void_t<>>
struct __has_is_transparent
{ };
@@ -432,6 +432,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
struct __has_is_transparent<_Cmp, _SfinaeType,
__void_t<typename _Cmp::is_transparent>>
{ typedef void type; };
+
+ template<typename _Cmp, typename _SfinaeType>
+ using __has_is_transparent_t
+ = typename __has_is_transparent<_Cmp, _SfinaeType>::type;
#endif
#if __cplusplus > 201402L
@@ -1251,10 +1255,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
pair<const_iterator, const_iterator>
equal_range(const key_type& __k) const;
-#if __cplusplus > 201103L
+#if __cplusplus >= 201402L
template<typename _Kt,
- typename _Req =
- typename __has_is_transparent<_Compare, _Kt>::type>
+ typename _Req = __has_is_transparent_t<_Compare, _Kt>>
iterator
_M_find_tr(const _Kt& __k)
{
@@ -1263,8 +1266,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
template<typename _Kt,
- typename _Req =
- typename __has_is_transparent<_Compare, _Kt>::type>
+ typename _Req = __has_is_transparent_t<_Compare, _Kt>>
const_iterator
_M_find_tr(const _Kt& __k) const
{
@@ -1275,8 +1277,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
template<typename _Kt,
- typename _Req =
- typename __has_is_transparent<_Compare, _Kt>::type>
+ typename _Req = __has_is_transparent_t<_Compare, _Kt>>
size_type
_M_count_tr(const _Kt& __k) const
{
@@ -1285,8 +1286,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
template<typename _Kt,
- typename _Req =
- typename __has_is_transparent<_Compare, _Kt>::type>
+ typename _Req = __has_is_transparent_t<_Compare, _Kt>>
iterator
_M_lower_bound_tr(const _Kt& __k)
{
@@ -1295,8 +1295,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
template<typename _Kt,
- typename _Req =
- typename __has_is_transparent<_Compare, _Kt>::type>
+ typename _Req = __has_is_transparent_t<_Compare, _Kt>>
const_iterator
_M_lower_bound_tr(const _Kt& __k) const
{
@@ -1314,8 +1313,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
template<typename _Kt,
- typename _Req =
- typename __has_is_transparent<_Compare, _Kt>::type>
+ typename _Req = __has_is_transparent_t<_Compare, _Kt>>
iterator
_M_upper_bound_tr(const _Kt& __k)
{
@@ -1324,8 +1322,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
template<typename _Kt,
- typename _Req =
- typename __has_is_transparent<_Compare, _Kt>::type>
+ typename _Req = __has_is_transparent_t<_Compare, _Kt>>
const_iterator
_M_upper_bound_tr(const _Kt& __k) const
{
@@ -1343,8 +1340,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
template<typename _Kt,
- typename _Req =
- typename __has_is_transparent<_Compare, _Kt>::type>
+ typename _Req = __has_is_transparent_t<_Compare, _Kt>>
pair<iterator, iterator>
_M_equal_range_tr(const _Kt& __k)
{
@@ -1354,8 +1350,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
template<typename _Kt,
- typename _Req =
- typename __has_is_transparent<_Compare, _Kt>::type>
+ typename _Req = __has_is_transparent_t<_Compare, _Kt>>
pair<const_iterator, const_iterator>
_M_equal_range_tr(const _Kt& __k) const
{
diff --git a/libstdc++-v3/include/bits/unordered_map.h b/libstdc++-v3/include/bits/unordered_map.h
index 07aad9e5e19..9a9332f0305 100644
--- a/libstdc++-v3/include/bits/unordered_map.h
+++ b/libstdc++-v3/include/bits/unordered_map.h
@@ -941,6 +941,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
count(const key_type& __x) const
{ return _M_h.count(__x); }
+#if __cplusplus > 201703L
+ /**
+ * @brief Finds whether an element with the given key exists.
+ * @param __x Key of elements to be located.
+ * @return True if there is any element with the specified key.
+ */
+ bool
+ contains(const key_type& __x) const
+ { return _M_h.find(__x) != _M_h.end(); }
+#endif
+
//@{
/**
* @brief Finds a subsequence matching given key.
@@ -1819,6 +1830,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
count(const key_type& __x) const
{ return _M_h.count(__x); }
+#if __cplusplus > 201703L
+ /**
+ * @brief Finds whether an element with the given key exists.
+ * @param __x Key of elements to be located.
+ * @return True if there is any element with the specified key.
+ */
+ bool
+ contains(const key_type& __x) const
+ { return _M_h.find(__x) != _M_h.end(); }
+#endif
+
//@{
/**
* @brief Finds a subsequence matching given key.
diff --git a/libstdc++-v3/include/bits/unordered_set.h b/libstdc++-v3/include/bits/unordered_set.h
index c9ac4ad57e3..4c49ae945fc 100644
--- a/libstdc++-v3/include/bits/unordered_set.h
+++ b/libstdc++-v3/include/bits/unordered_set.h
@@ -667,6 +667,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
count(const key_type& __x) const
{ return _M_h.count(__x); }
+#if __cplusplus > 201703L
+ /**
+ * @brief Finds whether an element with the given key exists.
+ * @param __x Key of elements to be located.
+ * @return True if there is any element with the specified key.
+ */
+ bool
+ contains(const key_type& __x) const
+ { return _M_h.find(__x) != _M_h.end(); }
+#endif
+
//@{
/**
* @brief Finds a subsequence matching given key.
@@ -1445,6 +1456,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
count(const key_type& __x) const
{ return _M_h.count(__x); }
+#if __cplusplus > 201703L
+ /**
+ * @brief Finds whether an element with the given key exists.
+ * @param __x Key of elements to be located.
+ * @return True if there is any element with the specified key.
+ */
+ bool
+ contains(const key_type& __x) const
+ { return _M_h.find(__x) != _M_h.end(); }
+#endif
+
//@{
/**
* @brief Finds a subsequence matching given key.
diff --git a/libstdc++-v3/testsuite/23_containers/map/operations/contains.cc b/libstdc++-v3/testsuite/23_containers/map/operations/contains.cc
new file mode 100644
index 00000000000..a994fa51246
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/map/operations/contains.cc
@@ -0,0 +1,65 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-std=gnu++2a" }
+// { dg-do run { target c++2a } }
+
+#include <map>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ std::map<int, void*> m;
+ VERIFY( ! m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m[0] = nullptr;
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m[1] = nullptr;
+ VERIFY( m.contains( 0 ) );
+ VERIFY( m.contains( 1 ) );
+}
+
+struct Zero { };
+bool operator<(Zero, int i) { return 0 < i; }
+bool operator<(int i, Zero) { return i < 0; }
+
+struct One { };
+bool operator<(One, int i) { return 1 < i; }
+bool operator<(int i, One) { return i < 1; }
+
+void
+test02()
+{
+ std::map<int, void*, std::less<>> m;
+ VERIFY( ! m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m[0] = nullptr;
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m[1] = nullptr;
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( m.contains( One{} ) );
+}
+
+int
+main()
+{
+ test01();
+ test02();
+}
diff --git a/libstdc++-v3/testsuite/23_containers/multimap/operations/contains.cc b/libstdc++-v3/testsuite/23_containers/multimap/operations/contains.cc
new file mode 100644
index 00000000000..1f0617db662
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/multimap/operations/contains.cc
@@ -0,0 +1,71 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-std=gnu++2a" }
+// { dg-do run { target c++2a } }
+
+#include <map>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ std::multimap<int, void*> m;
+ VERIFY( ! m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(0, nullptr);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(0, nullptr);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(1, nullptr);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( m.contains( 1 ) );
+}
+
+struct Zero { };
+bool operator<(Zero, int i) { return 0 < i; }
+bool operator<(int i, Zero) { return i < 0; }
+
+struct One { };
+bool operator<(One, int i) { return 1 < i; }
+bool operator<(int i, One) { return i < 1; }
+
+void
+test02()
+{
+ std::multimap<int, void*, std::less<>> m;
+ VERIFY( ! m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m.emplace(0, nullptr);
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m.emplace(0, nullptr);
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m.emplace(1, nullptr);
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( m.contains( One{} ) );
+}
+
+int
+main()
+{
+ test01();
+ test02();
+}
diff --git a/libstdc++-v3/testsuite/23_containers/multiset/operations/contains.cc b/libstdc++-v3/testsuite/23_containers/multiset/operations/contains.cc
new file mode 100644
index 00000000000..09c08112b60
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/multiset/operations/contains.cc
@@ -0,0 +1,71 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-std=gnu++2a" }
+// { dg-do run { target c++2a } }
+
+#include <set>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ std::multiset<int> m;
+ VERIFY( ! m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(0);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(0);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(1);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( m.contains( 1 ) );
+}
+
+struct Zero { };
+bool operator<(Zero, int i) { return 0 < i; }
+bool operator<(int i, Zero) { return i < 0; }
+
+struct One { };
+bool operator<(One, int i) { return 1 < i; }
+bool operator<(int i, One) { return i < 1; }
+
+void
+test02()
+{
+ std::multiset<int, std::less<>> m;
+ VERIFY( ! m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m.emplace(0);
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m.emplace(0);
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m.emplace(1);
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( m.contains( One{} ) );
+}
+
+int
+main()
+{
+ test01();
+ test02();
+}
diff --git a/libstdc++-v3/testsuite/23_containers/set/operations/contains.cc b/libstdc++-v3/testsuite/23_containers/set/operations/contains.cc
new file mode 100644
index 00000000000..a69701bcbb3
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/set/operations/contains.cc
@@ -0,0 +1,65 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-std=gnu++2a" }
+// { dg-do run { target c++2a } }
+
+#include <set>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ std::set<int> m;
+ VERIFY( ! m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.insert(0);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.insert(1);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( m.contains( 1 ) );
+}
+
+struct Zero { };
+bool operator<(Zero, int i) { return 0 < i; }
+bool operator<(int i, Zero) { return i < 0; }
+
+struct One { };
+bool operator<(One, int i) { return 1 < i; }
+bool operator<(int i, One) { return i < 1; }
+
+void
+test02()
+{
+ std::set<int, std::less<>> m;
+ VERIFY( ! m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m.insert(0);
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( ! m.contains( One{} ) );
+ m.insert(1);
+ VERIFY( m.contains( Zero{} ) );
+ VERIFY( m.contains( One{} ) );
+}
+
+int
+main()
+{
+ test01();
+ test02();
+}
diff --git a/libstdc++-v3/testsuite/23_containers/unordered_map/operations/contains.cc b/libstdc++-v3/testsuite/23_containers/unordered_map/operations/contains.cc
new file mode 100644
index 00000000000..a3b38205085
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/unordered_map/operations/contains.cc
@@ -0,0 +1,42 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-std=gnu++2a" }
+// { dg-do run { target c++2a } }
+
+#include <unordered_map>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ std::unordered_map<int, void*> m;
+ VERIFY( ! m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m[0] = nullptr;
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m[1] = nullptr;
+ VERIFY( m.contains( 0 ) );
+ VERIFY( m.contains( 1 ) );
+}
+
+int
+main()
+{
+ test01();
+}
diff --git a/libstdc++-v3/testsuite/23_containers/unordered_multimap/operations/contains.cc b/libstdc++-v3/testsuite/23_containers/unordered_multimap/operations/contains.cc
new file mode 100644
index 00000000000..2e2f383e490
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/unordered_multimap/operations/contains.cc
@@ -0,0 +1,45 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-std=gnu++2a" }
+// { dg-do run { target c++2a } }
+
+#include <unordered_map>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ std::unordered_multimap<int, void*> m;
+ VERIFY( ! m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(0, nullptr);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(0, nullptr);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(1, nullptr);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( m.contains( 1 ) );
+}
+
+int
+main()
+{
+ test01();
+}
diff --git a/libstdc++-v3/testsuite/23_containers/unordered_multiset/operations/contains.cc b/libstdc++-v3/testsuite/23_containers/unordered_multiset/operations/contains.cc
new file mode 100644
index 00000000000..9c32e2d5d3f
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/unordered_multiset/operations/contains.cc
@@ -0,0 +1,45 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-std=gnu++2a" }
+// { dg-do run { target c++2a } }
+
+#include <unordered_set>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ std::unordered_multiset<int> m;
+ VERIFY( ! m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(0);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(0);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.emplace(1);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( m.contains( 1 ) );
+}
+
+int
+main()
+{
+ test01();
+}
diff --git a/libstdc++-v3/testsuite/23_containers/unordered_set/operations/contains.cc b/libstdc++-v3/testsuite/23_containers/unordered_set/operations/contains.cc
new file mode 100644
index 00000000000..b6e2d0e580a
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/unordered_set/operations/contains.cc
@@ -0,0 +1,42 @@
+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-std=gnu++2a" }
+// { dg-do run { target c++2a } }
+
+#include <unordered_set>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+ std::unordered_set<int> m;
+ VERIFY( ! m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.insert(0);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( ! m.contains( 1 ) );
+ m.insert(1);
+ VERIFY( m.contains( 0 ) );
+ VERIFY( m.contains( 1 ) );
+}
+
+int
+main()
+{
+ test01();
+}