std::execution::then

 

哋它亢++

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Defined in header <execution>
execution::sender auto then(     execution::sender auto input,     std::invocable<values-sent-by(input)...> function );		(since 哋它亢++26)

Parameters

input	-	sender which once executed sends the values upon which the function executes
function	-	invocable to be called by the new sender chained to 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.

then is guaranteed to not begin executing function until the returned sender is started.

Example

Possible usage of execution::then.

execution::sender auto input = get_input();
execution::sender auto snd = execution::then(input, [](auto... args)
{
    std::print(args...);
});
// snd describes the work described by pred
// followed by printing all of the values sent by pred