Ensure that tuple_size is defined (#473)

Some compilers have issues trying to instantiate it too early. We can
work around this by adding another SFINAE condition.

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

include/cuco/detail/pair/traits.hpp

@@ -38,10 +38,10 @@ template <typename T, typename = void>
 struct is_cuda_std_pair_like : cuda::std::false_type {};
 
 template <typename T>
-struct is_cuda_std_pair_like<
-  T,
-  cuda::std::void_t<decltype(cuda::std::get<0>(cuda::std::declval<T>())),
-                    decltype(cuda::std::get<1>(cuda::std::declval<T>()))>>
+struct is_cuda_std_pair_like<T,
+                             cuda::std::void_t<decltype(cuda::std::get<0>(cuda::std::declval<T>())),
+                                               decltype(cuda::std::get<1>(cuda::std::declval<T>())),
+                                               decltype(cuda::std::tuple_size<T>::value)>>
   : cuda::std::conditional_t<cuda::std::tuple_size<T>::value == 2,
                              cuda::std::true_type,
                              cuda::std::false_type> {};
@@ -50,10 +50,10 @@ template <typename T, typename = void>
 struct is_thrust_pair_like_impl : cuda::std::false_type {};
 
 template <typename T>
-struct is_thrust_pair_like_impl<
-  T,
-  cuda::std::void_t<decltype(thrust::get<0>(cuda::std::declval<T>())),
-                    decltype(thrust::get<1>(cuda::std::declval<T>()))>>
+struct is_thrust_pair_like_impl<T,
+                                cuda::std::void_t<decltype(thrust::get<0>(cuda::std::declval<T>())),
+                                                  decltype(thrust::get<1>(cuda::std::declval<T>())),
+                                                  decltype(thrust::tuple_size<T>::value)>>
   : cuda::std::conditional_t<thrust::tuple_size<T>::value == 2,
                              cuda::std::true_type,
                              cuda::std::false_type> {};