std::execution::seq, std::execution::par, std::execution::par_unseq, std::execution::unseq

Defined in header <execution>
inline constexpr std::execution::sequenced_policy seq { /* unspecified */ };
(since C++17)
inline constexpr std::execution::parallel_policy par { /* unspecified */ };
(since C++17)
inline constexpr std::execution::parallel_unsequenced_policy par_unseq { /* unspecified */ };
(since C++17)
inline constexpr std::execution::unsequenced_policy unseq { /* unspecified */ };
(since C++20)

std::execution::seq, std::execution::par, std::execution::par_unseq, and std::execution::unseq are instances of the execution policy types std::execution::sequenced_policy, std::execution::parallel_policy, std::execution::parallel_unsequenced_policy, and std::execution::unsequenced_policy respectively. They are used to specify the execution policy of parallel algorithms - i.e., the kinds of parallelism allowed.

Additional execution policies may be provided by a standard library implementation (possible future additions may include std::parallel::cuda and std::parallel::opencl).

See also

(C++17)(C++17)(C++17)(C++20)
execution policy types
(class)

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