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experimental::as_single_t::as_single_t (1 of 2 overloads)

Default constructor.

constexpr as_single_t(
    default_constructor_tag  = default_constructor_tag(),
    CompletionToken token = CompletionToken());

This constructor is only valid if the underlying completion token is default constructible and move constructible. The underlying completion token is itself defaulted as an argument to allow it to capture a source location.