xref: /llvm-project/libcxx/test/std/containers/unord/unord.set/hash_function.pass.cpp (revision be4adb5c2b77b66786617e101e6a845cc587b0a8)
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 // <unordered_set>
10 
11 // template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
12 //           class Alloc = allocator<Value>>
13 // class unordered_set
14 
15 // hasher hash_function() const;
16 
17 #include <unordered_set>
18 #include <cassert>
19 
main(int,char **)20 int main(int, char**) {
21   typedef std::unordered_set<int> set_type;
22   set_type s;
23 
24   std::pair<set_type::iterator, bool> p = s.insert(1);
25 
26   const set_type& cs = s;
27   assert(cs.hash_function()(*p.first) == cs.hash_function()(1));
28   assert(cs.hash_function()(1) == cs.hash_function()(*p.first));
29 
30   return 0;
31 }
32