 {
   auto t = std::make_tuple(0, 2, 3.14);
 
-  thrust::tuple_for_each(t, [](auto& x) { x *= x; }); 
+  thrust::tuple_for_each(t, custom_square_inplace{});
 
   ASSERT_EQUAL_QUIET(t, std::make_tuple(0, 4, 9.8596));
 }
 DECLARE_UNITTEST(test_tuple_for_each);
- 
+
 #endif // THRUST_CPP_DIALECT >= 2011
 

{
  auto t0 = std::make_tuple(0, 2, 3.14);

  auto t1 = thrust::tuple_subset(t0, std::index_sequence<2, 0>{}); 

  ASSERT_EQUAL_QUIET(t1, std::make_tuple(3.14, 0));
}

#include <unittest/unittest.h>

#include <thrust/detail/tuple_algorithms.h>
#include <thrust/type_traits/integer_sequence.h>

// FIXME: Replace with C++14 style `thrust::square<>` when we have it.
struct custom_square
{
  template <typename T>
  __host__ __device__
  T operator()(T v) const
  {
    return v * v;
  }
};

struct custom_square_inplace
{
  template <typename T>
  __host__ __device__
  void operator()(T& v) const
  {
    v *= v;
  }
};

