std::experimental::parallel::sequential_execution_policy, std::experimental::parallel::parallel_execution_policy, std::experimental::parallel::parallel_vector_execution_policy

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Technical specifications
Filesystem library (filesystem TS)
Library fundamentals (library fundamentals TS)
Library fundamentals 2 (library fundamentals TS v2)
Library fundamentals 3 (library fundamentals TS v3)
Extensions for parallelism (parallelism TS)
Extensions for parallelism 2 (parallelism TS v2)
Extensions for concurrency (concurrency TS)
Extensions for concurrency 2 (concurrency TS v2)
Concepts (concepts TS)
Ranges (ranges TS)
Reflection (reflection TS)
Mathematical special functions (special functions TR)
 
 
class sequential_execution_policy { /* unspecified */ };
(parallelism TS)
class parallel_execution_policy { /* unspecified */ };
(parallelism TS)
class parallel_vector_execution_policy { /* unspecified */ };
(parallelism TS)

sequential_execution_policy, parallel_execution_policy and parallel_vector_execution_policy are tag types used to indicate the kinds of parallelism allowed in the execution of a parallel algorithm.