thrust::host_execution_policy< DerivedPolicy > Struct Template Reference

#include <thrust/execution_policy.h>

Detailed Description

template<typename DerivedPolicy>
struct thrust::host_execution_policy< DerivedPolicy >

host_execution_policy is the base class for all Thrust parallel execution policies which are derived from Thrust's default host backend system configured with the THRUST_HOST_SYSTEM macro.

Custom user-defined backends which wish to inherit the functionality of Thrust's host backend system should derive a policy from this type in order to interoperate with Thrust algorithm dispatch.

The following code snippet demonstrates how to derive a standalone custom execution policy from thrust::host_execution_policy to implement a backend which specializes for_each while inheriting the behavior of every other algorithm from the host system:

#include <iostream>
// define a type derived from thrust::host_execution_policy to distinguish our custom execution policy:
struct my_policy : thrust::host_execution_policy<my_policy> {};
// overload for_each on my_policy
template<typename Iterator, typename Function>
Iterator for_each(my_policy, Iterator first, Iterator last, Function f)
std::cout << "Hello, world from for_each(my_policy)!" << std::endl;
for(; first < last; ++first)
return first;
struct ignore_argument
void operator()(int) {}
int main()
int data[4];
// dispatch thrust::for_each using our custom policy:
my_policy exec;
thrust::for_each(exec, data, data + 4, ignore_argument());
// dispatch thrust::transform whose behavior our policy inherits
thrust::transform(exec, data, data, + 4, data, thrust::identity<int>());
return 0;
See also

The documentation for this struct was generated from the following file: