I want to disable copy constructor of some template class conditionally. In other words, I want disable copy constructor, if base type is not copy constructible. To solve such problem (in educational purposes) I decided to write following program. (Here is link to ideone http://ift.tt/2y8yjyY) Below is source of my program:
#include <algorithm>
#include <type_traits>
using namespace std;
template <typename Data>
class Container
{
public:
typedef Container<Data> self_type;
Container():
m_data()
{
}
Container(const typename
std::enable_if<std::is_copy_constructible<Data>::value,
self_type>::type& other_data) :
m_data(other_data.m_data)
{
}
Container(self_type&& other)
{
std::swap(m_data, other.m_data);
}
private:
Data m_data;
};
class SomeData
{
public:
SomeData(){}
SomeData(const SomeData&) = delete;
};
int main()
{
Container<SomeData> container;
return 0;
}
But message from compiler really confuses me:
prog.cpp: In instantiation of ‘class Container’: prog.cpp:41:22: required from here prog.cpp:17:2: error: no type named ‘type’ in ‘struct std::enable_if >’ Container(const typename std::enable_if::value
As I understand it should lead to SFINAE and nothing should be arised from compiler. Where am I wrong?
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