std::execution::let_value

 

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Execution concepts scheduler receiver receiver_of operation_state    sender sender_in sender_to Execution components Execution contexts run_loop Execution domains default_domain Forward progress guarantee forward_progress_guarantee Environments empty_env    get_env    env_of_t Queries std::stop_token_of_t std::get_stop_token std::get_allocator std::forwarding_query get_scheduler get_domain get_forward_progress_guarantee get_delegation_scheduler get_completion_scheduler Completion signatures completion_signatures completion_signatures_of_t transform_completion_signatures transform_completion_signatures_of    value_types_of_t error_types_of_t    tag_of_t sends_stopped    Sender adaptor closures sender_adaptor_closure Coroutine utility as_awaitable with_awaitable_senders

Core operations Operation state connect connect_result_t start Completion set_value set_error set_stopped Transformation transform_env transform_sender apply_sender Sender algorithms Sender factories just just_error just_stopped read_env schedule schedule_result_t Sender adaptors starts_on continues_on    on then upon_error upon_stopped let_value let_error let_stopped schedule_from when_all when_all_with_variant into_variant stopped_as_optional stopped_as_error bulk split Sender consumers this_thread::sync_wait this_thread::sync_wait_with_variant

 

Defined in header <execution>
execution::sender auto     let_value( execution::sender auto input,                std::invocable</*values-sent-by*/(input)...> function );		(since C++26)

Parameters

input	-	sender which once executed sends the values upon which the function executes
function	-	invocable to be called with the values from the input sender

Return value

Returns a sender describing the task graph described by the input sender, with an added node of invoking the provided function with the values sent by the input sender as arguments.

let_value is similar to then, however, where the sender returned from then sends exactly what that function ends up returning - let_value requires that the function returns a sender, and the sender returned by let_value sends the values sent by the sender returned from the callback.