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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <iterator>
// Test fails due to use of is_trivially_* trait.
// XFAIL: gcc-4.9
// template <class T, class charT = char, class traits = char_traits<charT>,
// class Distance = ptrdiff_t>
// class istream_iterator
// : public iterator<input_iterator_tag, T, Distance, const T*, const T&>
// {
// public:
// typedef charT char_type;
// typedef traits traits_type;
// typedef basic_istream<charT,traits> istream_type;
// ...
//
// Before C++17, we have:
// If T is a literal type, then the default constructor shall be a constexpr constructor.
// If T is a literal type, then this constructor shall be a trivial copy constructor.
// If T is a literal type, then this destructor shall be a trivial destructor.
// C++17 says:
// If is_trivially_default_constructible_v<T> is true, then
// this constructor (the default ctor) is a constexpr constructor.
// If is_trivially_copy_constructible_v<T> is true, then
// this constructor (the copy ctor) is a trivial copy constructor.
// If is_trivially_destructible_v<T> is true, then this
// destructor is a trivial destructor.
// Testing the C++17 ctors for this are in the ctor tests.
#include <iterator>
#include <type_traits>
#include <string>
int main()
{
typedef std::istream_iterator<double> I1; // double is trivially destructible
static_assert((std::is_convertible<I1,
std::iterator<std::input_iterator_tag, double, std::ptrdiff_t,
const double*, const double&> >::value), "");
static_assert((std::is_same<I1::char_type, char>::value), "");
static_assert((std::is_same<I1::traits_type, std::char_traits<char> >::value), "");
static_assert((std::is_same<I1::istream_type, std::istream>::value), "");
static_assert( std::is_trivially_copy_constructible<I1>::value, "");
static_assert( std::is_trivially_destructible<I1>::value, "");
typedef std::istream_iterator<unsigned, wchar_t> I2; // unsigned is trivially destructible
static_assert((std::is_convertible<I2,
std::iterator<std::input_iterator_tag, unsigned, std::ptrdiff_t,
const unsigned*, const unsigned&> >::value), "");
static_assert((std::is_same<I2::char_type, wchar_t>::value), "");
static_assert((std::is_same<I2::traits_type, std::char_traits<wchar_t> >::value), "");
static_assert((std::is_same<I2::istream_type, std::wistream>::value), "");
static_assert( std::is_trivially_copy_constructible<I2>::value, "");
static_assert( std::is_trivially_destructible<I2>::value, "");
typedef std::istream_iterator<std::string> I3; // string is NOT trivially destructible
static_assert(!std::is_trivially_copy_constructible<I3>::value, "");
static_assert(!std::is_trivially_destructible<I3>::value, "");
}
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