Experimental library header <experimental/execution>

 

C++

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Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Execution support library (C++26)

Technical specifications

Symbols index

External libraries

 

Standard library headers

Language support <cfloat> <climits> <compare> (C++20) <coroutine> (C++20) <csetjmp> <csignal> <cstdarg> <cstddef> <cstdint> (C++11) <cstdlib> <exception> <initializer_list> (C++11)    <limits> <new> <source_location> (C++20) <stdfloat> (C++23) <typeinfo> <version> (C++20) Concepts <concepts> (C++20) Diagnostics <cassert> <cerrno> <debugging> (C++26) <stacktrace> (C++23) <stdexcept> <system_error> (C++11) Memory management <memory> <memory_resource> (C++17) <scoped_allocator> (C++11) Metaprogramming <type_traits> (C++11) <ratio> (C++11)

General utilities <any> (C++17) <bitset> <bit> (C++20) <charconv> (C++17) <expected> (C++23) <format> (C++20) <functional> <optional> (C++17) <tuple> (C++11) <typeindex> (C++11) <utility> <variant> (C++17) Containers <array> (C++11) <deque> <flat_map> (C++23) <flat_set> (C++23) <forward_list> (C++11) <inplace_vector> (C++26)    <list> <map> <mdspan> (C++23) <queue> <set> <span> (C++20) <stack> <unordered_map> (C++11) <unordered_set> (C++11) <vector> Iterators <iterator> Ranges <generator> (C++23) <ranges> (C++20)

Algorithms <algorithm> <numeric> Strings <cctype> <cstring> <cuchar> (C++11) <cwchar> <cwctype> <string_view> (C++17) <string> Text processing <clocale> <codecvt> (C++11/17/26*) <locale> <regex> (C++11) <text_encoding> (C++26)    Numerics <cfenv> (C++11) <cmath> <complex> <linalg> (C++26) <numbers> (C++20) <random> (C++11) <valarray> Time <chrono> (C++11) <ctime> C compatibility <ccomplex> (C++11/17/20*) <ciso646> (until C++20) <cstdalign> (C++11/17/20*) <cstdbool> (C++11/17/20*) <ctgmath> (C++11/17/20*)

Input/output <cinttypes> (C++11) <cstdio> <filesystem> (C++17) <fstream> <iomanip> <iosfwd> <iostream> <ios> <istream> <ostream> <print> (C++23) <spanstream> (C++23) <sstream> <streambuf> <strstream> (C++98/26*) <syncstream> (C++20) Concurrency support <atomic> (C++11) <barrier> (C++20) <condition_variable> (C++11) <future> (C++11) <hazard_pointer> (C++26) <latch> (C++20) <mutex> (C++11) <rcu> (C++26) <semaphore> (C++20) <shared_mutex> (C++14) <stdatomic.h> (C++23) <stop_token> (C++20) <thread> (C++11) Execution support <execution> (C++17)

 

Experimental library headers

Execution P2300
<experimental/execution>
Filesystem TS
<experimental/filesystem>
Parallelism TS (v1, v2)
experimental/algorithm experimental/execution_policy experimental/exception_list	experimental/numeric <experimental/simd> experimental/task_block
Library Fundamentals TS (v1, v2, v3)
experimental/algorithm <experimental/any> experimental/array experimental/chrono experimental/deque experimental/forward_list <experimental/functional> experimental/future experimental/iterator experimental/list experimental/map experimental/memory <experimental/memory_resource> experimental/numeric <experimental/optional> experimental/propagate_const	experimental/random experimental/ratio experimental/regex experimental/scope experimental/set experimental/source_location experimental/string <experimental/string_view> experimental/system_error experimental/tuple experimental/type_traits experimental/unordered_map experimental/unordered_set experimental/utility experimental/vector
Concurrency TS
experimental/atomic experimental/barrier	experimental/future experimental/latch
Ranges TS
<experimental/ranges/algorithm> <experimental/ranges/concepts> <experimental/ranges/functional>         <experimental/ranges/iterator>	<experimental/ranges/random> <experimental/ranges/tuple> <experimental/ranges/type_traits> <experimental/ranges/utility>
Coroutines TS
experimental/coroutine
Networking TS
experimental/buffer experimental/executor experimental/internet experimental/io_context	<experimental/net> experimental/netfwd experimental/socket experimental/timer
Reflection TS
<experimental/reflect>

 

This header is part of execution library, based on P2300R7.

Includes

Synopsis

namespace std {
  // helper concepts
  template<class T>
    concept /*movable-value*/ = /*see-below*/; // exposition only
 
  template<class From, class To>
    concept /*decays-to*/ = same_as<decay_t<From>, To>; // exposition only
 
  template<class T>
    concept /*class-type*/ = /*decays-to*/<T, T> && is_class_v<T>;  // exposition only
 
  // queryable objects
  template<class T>
    concept queryable = destructible;
 
  // queries
  namespace queries { // exposition only
    struct forwarding_query_t;
    struct get_allocator_t;
    struct get_stop_token_t;
  }
  using queries::forwarding_query_t;
  using queries::get_allocator_t;
  using queries::get_stop_token_t;
  inline constexpr forwarding_query_t forwarding_query{};
  inline constexpr get_allocator_t get_allocator{};
  inline constexpr get_stop_token_t get_stop_token{};
 
  template<class T>
    using stop_token_of_t =
      remove_cvref_t<decltype(get_stop_token(declval<T>()))>;
 
  template<class T>
    concept /*forwarding-query*/ = // exposition only
      forwarding_query(T{});
 
  namespace /*exec-envs*/ { // exposition only
    struct empty_env {};
    struct get_env_t;
  }
  using /*exec-envs*/::empty_env;
  using /*exec-envs*/::get_env_t;
  inline constexpr get_env_t get_env {};
 
  template<class T>
    using env_of_t = decltype(get_env(declval<T>()));
}
 
namespace std::execution {
  // queries
  enum class forward_progress_guarantee;
  namespace queries { // exposition only
    struct get_scheduler_t;
    struct get_delegatee_scheduler_t;
    struct get_forward_progress_guarantee_t;
    template<class CPO>
      struct get_completion_scheduler_t;
  }
  using queries::get_scheduler_t;
  using queries::get_delegatee_scheduler_t;
  using queries::get_forward_progress_guarantee_t;
  using queries::get_completion_scheduler_t;
  inline constexpr get_scheduler_t get_scheduler{};
  inline constexpr get_delegatee_scheduler_t get_delegatee_scheduler{};
  inline constexpr get_forward_progress_guarantee_t get_forward_progress_guarantee{};
  template<class CPO>
    inline constexpr get_completion_scheduler_t<CPO> get_completion_scheduler{};
 
  // schedulers
  template<class S>
    concept scheduler = /*see-below*/;
 
  // receivers
  template<class R>
    inline constexpr bool enable_receiver = /*see-below*/;
 
  template<class R>
    concept receiver = /*see-below*/;
 
  template<class R, class Completions>
    concept receiver_of = /*see-below*/;
 
  namespace receivers { // exposition only
    struct set_value_t;
    struct set_error_t;
    struct set_stopped_t;
  }
  using receivers::set_value_t;
  using receivers::set_error_t;
  using receivers::set_stopped_t;
  inline constexpr set_value_t set_value{};
  inline constexpr set_error_t set_error{};
  inline constexpr set_stopped_t set_stopped{};
 
  // operation states
  template<class O>
    concept operation_state = /*see-below*/;
 
  namespace /*op-state*/ { // exposition only
    struct start_t;
  }
  using /*op-state*/::start_t;
  inline constexpr start_t start{};
 
  // senders
  template<class S>
    inline constexpr bool enable_sender = /* see description */;
 
  template<class S>
    concept sender = /*see-below*/;
 
  template<class S, class E = empty_env>
    concept sender_in = /*see-below*/;
 
  template<class S, class R>
    concept sender_to = /*see-below*/;
 
  template <class S, class Sig, class E = empty_env>
    concept sender_of = /* see description */;
 
  template<class... Ts>
    struct /*type-list*/; // exposition only
 
  template<class S, class E = empty_env>
    using /*single-sender-value-type*/ = /* see description */; // exposition only
 
  template<class S, class E = empty_env>
    concept /*single-sender*/ = /* see description */; // exposition only
 
  // completion signatures
  namespace /*completion-signatures*/ { // exposition only
    struct get_completion_signatures_t;
  }
  using /*completion-signatures*/::get_completion_signatures_t;
  inline constexpr get_completion_signatures_t get_completion_signatures {};
 
  template<class S, class E = empty_env>
      requires sender_in<S, E>
    using completion_signatures_of_t = /*call-result-t*/<get_completion_signatures_t, S, E>;
 
  template<class... Ts>
    using /*decayed-tuple*/ = tuple<decay_t<Ts>...>; // exposition only
 
  template<class... Ts>
    using /*variant-or-empty*/ = /* see description */; // exposition only
 
  template<class S,
           class E = empty_env,
           template<class...> class Tuple = /*decayed-tuple*/,
           template<class...> class Variant = /*variant-or-empty*/>
      requires sender_in<S, E>
    using value_types_of_t = /* see description */;
 
  template<class S,
           class Env = empty_env,
           template<class...> class Variant = /*variant-or-empty*/>
      requires sender_in<S, E>
    using error_types_of_t = /* see description */;
 
  template<class S, class E = empty_env>
      requires sender_in<S, E>
    inline constexpr bool sends_stopped = /* see description */;
 
  // the connect sender algorithm
  namespace /*senders-connect*/ { // exposition only
    struct connect_t;
  }
  using /*senders-connect*/::connect_t;
  inline constexpr connect_t connect{};
 
  template<class S, class R>
    using connect_result_t = decltype(connect(declval<S>(), declval<R>()));
 
  // sender factories
  namespace /*senders-factories*/ { // exposition only
    struct schedule_t;
    struct transfer_just_t;
  }
  inline constexpr /* unspecified */ just{};
  inline constexpr /* unspecified */ just_error{};
  inline constexpr /* unspecified */ just_stopped{};
  using /*senders-factories*/::schedule_t;
  using /*senders-factories*/::transfer_just_t;
  inline constexpr schedule_t schedule{};
  inline constexpr transfer_just_t transfer_just{};
  inline constexpr /* unspecified */ read{};
 
  template<scheduler S>
    using schedule_result_t = decltype(schedule(declval<S>()));
 
  // sender adaptors
  namespace /*sender-adaptor-closure*/ { // exposition only
    template</*class-type*/ D>
      struct sender_adaptor_closure { };
  }
  using /*sender-adaptor-closure*/::sender_adaptor_closure;
 
  namespace /*sender-adaptors*/ { // exposition only
    struct on_t;
    struct transfer_t;
    struct schedule_from_t;
    struct then_t;
    struct upon_error_t;
    struct upon_stopped_t;
    struct let_value_t;
    struct let_error_t;
    struct let_stopped_t;
    struct bulk_t;
    struct split_t;
    struct when_all_t;
    struct when_all_with_variant_t;
    struct transfer_when_all_t;
    struct transfer_when_all_with_variant_t;
    struct into_variant_t;
    struct stopped_as_optional_t;
    struct stopped_as_error_t;
    struct ensure_started_t;
  }
  using /*sender-adaptors*/::on_t;
  using /*sender-adaptors*/::transfer_t;
  using /*sender-adaptors*/::schedule_from_t;
  using /*sender-adaptors*/::then_t;
  using /*sender-adaptors*/::upon_error_t;
  using /*sender-adaptors*/::upon_stopped_t;
  using /*sender-adaptors*/::let_value_t;
  using /*sender-adaptors*/::let_error_t;
  using /*sender-adaptors*/::let_stopped_t;
  using /*sender-adaptors*/::bulk_t;
  using /*sender-adaptors*/::split_t;
  using /*sender-adaptors*/::when_all_t;
  using /*sender-adaptors*/::when_all_with_variant_t;
  using /*sender-adaptors*/::transfer_when_all_t;
  using /*sender-adaptors*/::transfer_when_all_with_variant_t;
  using /*sender-adaptors*/::into_variant_t;
  using /*sender-adaptors*/::stopped_as_optional_t;
  using /*sender-adaptors*/::stopped_as_error_t;
  using /*sender-adaptors*/::ensure_started_t;
 
  inline constexpr on_t on{};
  inline constexpr transfer_t transfer{};
  inline constexpr schedule_from_t schedule_from{};
 
  inline constexpr then_t then{};
  inline constexpr upon_error_t upon_error{};
  inline constexpr upon_stopped_t upon_stopped{};
 
  inline constexpr let_value_t let_value{};
  inline constexpr let_error_t let_error{};
  inline constexpr let_stopped_t let_stopped{};
 
  inline constexpr bulk_t bulk{};
 
  inline constexpr split_t split{};
  inline constexpr when_all_t when_all{};
  inline constexpr when_all_with_variant_t when_all_with_variant{};
  inline constexpr transfer_when_all_t transfer_when_all{};
  inline constexpr transfer_when_all_with_variant_t
    transfer_when_all_with_variant{};
 
  inline constexpr into_variant_t into_variant{};
 
  inline constexpr stopped_as_optional_t stopped_as_optional;
 
  inline constexpr stopped_as_error_t stopped_as_error;
 
  inline constexpr ensure_started_t ensure_started{};
 
  // sender consumers
  namespace /*sender-consumers*/ { // exposition only
    struct start_detached_t;
  }
  using /*sender-consumers*/::start_detached_t;
  inline constexpr start_detached_t start_detached{};
 
  // sender and receiver utilities
  // [exec.utils.rcvr.adptr]
  template<
      /*class-type*/ Derived,
      receiver Base = /* unspecified */> // arguments are not associated entities
    class receiver_adaptor;
 
  template<class Fn>
    concept /*completion-signature*/ = // exposition only
      /* see description */;
 
  // [exec.utils.cmplsigs]
  template</*completion-signature*/... Fns>
    struct completion_signatures {};
 
  template<class... Args> // exposition only
    using /*default-set-value*/ =
      completion_signatures<set_value_t(Args...)>;
 
  template<class Err> // exposition only
    using /*default-set-error*/ =
      completion_signatures<set_error_t(Err)>;
 
  template<class Sigs> // exposition only
    concept /*valid-completion-signatures*/ = /* see description */;
 
  // [exec.utils.mkcmplsigs]
  template<
    sender Sndr,
    class Env = empty_env,
    /*valid-completion-signatures*/ AddlSigs = completion_signatures<>,
    template<class...> class SetValue = /* see description */,
    template<class> class SetError = /* see description */,
    /*valid-completion-signatures*/ SetStopped = completion_signatures<set_stopped_t()>>
      requires sender_in<Sndr, Env>
  using make_completion_signatures = completion_signatures</* see description */>;
 
  // execution resources
  class run_loop;
}
 
namespace std::this_thread {
  // queries
  namespace queries { // exposition only
    struct execute_may_block_caller_t;
  }
  using queries::execute_may_block_caller_t;
  inline constexpr execute_may_block_caller_t execute_may_block_caller{};
 
  namespace /*this-thread*/ { // exposition only
    struct /*sync-wait-env*/; // exposition only
    template<class S>
        requires sender_in<S, /*sync-wait-env*/>
      using /*sync-wait-type*/ = /*see-below*/; // exposition only
    template<class S>
      using /*sync-wait-with-variant-type*/ = /*see-below*/; // exposition only
 
    struct sync_wait_t;
    struct sync_wait_with_variant_t;
  }
  using /*this-thread*/::sync_wait_t;
  using /*this-thread*/::sync_wait_with_variant_t;
  inline constexpr sync_wait_t sync_wait{};
  inline constexpr sync_wait_with_variant_t sync_wait_with_variant{};
}
 
namespace std::execution {
  // one-way execution
  namespace execute { // exposition only
    struct execute_t;
  }
  using execute::execute_t;
  inline constexpr execute_t execute{};
 
  // [exec.as.awaitable]
  namespace /*coro-utils*/ { // exposition only
    struct as_awaitable_t;
  }
  using /*coro-utils*/::as_awaitable_t;
  inline constexpr as_awaitable_t as_awaitable;
 
  // [exec.with.awaitable.senders]
  template</*class-type*/ Promise>
    struct with_awaitable_senders;
}