Home | History | Annotate | Download | only in unord.hash
      1 //===----------------------------------------------------------------------===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is dual licensed under the MIT and the University of Illinois Open
      6 // Source Licenses. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 
     10 // <functional>
     11 
     12 // template <class T>
     13 // struct hash
     14 //     : public unary_function<T, size_t>
     15 // {
     16 //     size_t operator()(T val) const;
     17 // };
     18 
     19 // Not very portable
     20 
     21 #include <functional>
     22 #include <cassert>
     23 #include <type_traits>
     24 #include <limits>
     25 
     26 template <class T>
     27 void
     28 test()
     29 {
     30     typedef std::hash<T> H;
     31     static_assert((std::is_same<typename H::argument_type, T>::value), "" );
     32     static_assert((std::is_same<typename H::result_type, std::size_t>::value), "" );
     33     H h;
     34 
     35     typedef typename std::remove_pointer<T>::type type;
     36     type i;
     37     type j;
     38     assert(h(&i) != h(&j));
     39 }
     40 
     41 int main()
     42 {
     43     test<int*>();
     44 }
     45