test_result_of.cpp

来自「Boost provides free peer-reviewed portab」· C++ 代码 · 共 54 行

//  (C) Copyright John Maddock 2005.
//  Use, modification and distribution are subject to the
//  Boost Software License, Version 1.0. (See accompanying file
//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

#ifdef TEST_STD_HEADERS
#include <functional>
#else
#include <boost/tr1/functional.hpp>
#endif

#include <boost/static_assert.hpp>
#include <boost/type_traits/is_same.hpp>

struct int_result_type { typedef int result_type; };

struct int_result_of
{
  template<typename F> struct result { typedef int type; };
};

struct int_result_type_and_float_result_of
{
  typedef int result_type;
  template<typename F> struct result { typedef float type; };
};

struct X {};

int main()
{
  typedef int (*func_ptr)(float, double);
  typedef int (&func_ref)(float, double);
  typedef int (X::*mem_func_ptr)(float);
  typedef int (X::*mem_func_ptr_c)(float) const;
  typedef int (X::*mem_func_ptr_v)(float) volatile;
  typedef int (X::*mem_func_ptr_cv)(float) const volatile;

  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<int_result_type(float)>::type, int>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<int_result_of(double)>::type, int>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<int_result_of(void)>::type, void>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<const int_result_of(double)>::type, int>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<volatile int_result_of(void)>::type, void>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<int_result_type_and_float_result_of(char)>::type, int>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<func_ptr(char, float)>::type, int>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<func_ref(char, float)>::type, int>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<mem_func_ptr(X,char)>::type, int>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<mem_func_ptr_c(X,char)>::type, int>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<mem_func_ptr_v(X,char)>::type, int>::value));
  BOOST_STATIC_ASSERT((::boost::is_same< ::std::tr1::result_of<mem_func_ptr_cv(X,char)>::type, int>::value));
  return 0;
}