std::experimental::parallel::seq, std::experimental::parallel::par, std::experimental::parallel::

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C++
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Filesystem library (filesystem TS)
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Extensions for parallelism
constexpr sequential_execution_policy seq{};
 (parallelism TS)
constexpr parallel_execution_policy par{};
 (parallelism TS)
constexpr parallel_vector_execution_policy par_vec{};
 (parallelism TS)

seq, par and par_vec are instances of the execution policy types sequential_execution_policy, parallel_execution_policy and parallel_vector_execution_policy

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