1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9// UNSUPPORTED: c++03, c++11
10
11// <set>
12
13// class set
14
15// template<typename K>
16// pair<iterator,iterator> equal_range(const K& x); //
17// C++14
18// template<typename K>
19// pair<const_iterator,const_iterator> equal_range(const K& x) const; //
20// C++14
21
22#include <cassert>
23#include <set>
24#include <utility>
25
26struct Comp {
27 using is_transparent = void;
28
29 bool operator()(const std::pair<int, int>& lhs, const std::pair<int, int>& rhs) const { return lhs < rhs; }
30
31 bool operator()(const std::pair<int, int>& lhs, int rhs) const { return lhs.first < rhs; }
32
33 bool operator()(int lhs, const std::pair<int, int>& rhs) const { return lhs < rhs.first; }
34};
35
36int main(int, char**) {
37 std::set<std::pair<int, int>, Comp> s{{2, 1}, {1, 2}, {1, 3}, {1, 4}, {2, 2}};
38
39 auto er = s.equal_range(x: 1);
40 long nels = 0;
41
42 for (auto it = er.first; it != er.second; it++) {
43 assert(it->first == 1);
44 nels++;
45 }
46
47 assert(nels == 3);
48
49 return 0;
50}
51

source code of libcxx/test/std/containers/associative/set/equal_range_transparent.pass.cpp