1 #ifndef __JLANG__JRESOLVE__
2 #define __JLANG__JRESOLVE__
10 namespace JPP {
using namespace JLANG; }
20 template<
class U>
static auto exists(U*) -> decltype(
sizeof(U) >= 0);
21 template<
typename>
static auto exists(...) -> std::false_type;
24 static const bool value = std::is_same<bool, decltype(exists<T>(0))>
::value;
Test existence of class T.
static auto exists(U *) -> decltype(sizeof(U) >=0)
static const bool value
true if an implementation of class T exists; else false