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#include <stdint.h>
#include <iostream>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <sstream>
#include <algorithm>
#include <iterator>
using namespace std;
template <int x>
struct IntType
{
enum
{
value = x
};
};
template <typename T>
class TypeTrait
{
template <typename U> struct Type
{
enum { isPointer = false };
enum { isConst = false };
typedef U Plain;
};
template <typename U> struct Type<U const>
{
enum { isPointer = false };
enum { isConst = true };
typedef U Plain;
};
typedef char small;
struct Big {char big[2];};
template <typename T2>
static small fun(...);
template <typename T2>
static Big fun(void (T2::*)());
// template <typename T2>
// static IntType<false> fun(...);
//
// template <typename T2>
// static IntType<true> fun(void (T2::*)());
public:
enum { isConst = Type<T>::isConst };
enum { isClass = sizeof(fun<T>(0)) == sizeof(Big) };
// enum { isClass = fun<T>(0)::value;
};
int main()
{
string s;
cout << TypeTrait<string>::isClass << '\n';
cout << TypeTrait<int>::isClass << '\n';
}
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