optional.hpp

Go to the documentation of this file.

// SPDX-FileCopyrightText: 2006-2024 Knut Reinert & Freie Universität Berlin
// SPDX-FileCopyrightText: 2016-2024 Knut Reinert & MPI für molekulare Genetik
// SPDX-License-Identifier: BSD-3-Clause
 
#pragma once
 
#include <optional>
 
#include <seqan3/core/debug_stream/debug_stream_type.hpp>
#include <seqan3/core/detail/template_inspection.hpp>
#include <seqan3/utility/type_traits/basic.hpp>
 
namespace seqan3
{
template <typename char_t>
inline debug_stream_type<char_t> & operator<<(debug_stream_type<char_t> & s, std::nullopt_t SEQAN3_DOXYGEN_ONLY(arg))
{
    s << "<VALUELESS_OPTIONAL>";
    return s;
}
 
template <typename char_t, typename optional_type>
    requires detail::is_type_specialisation_of_v<std::remove_cvref_t<optional_type>, std::optional>
inline debug_stream_type<char_t> & operator<<(debug_stream_type<char_t> & s, optional_type && arg)
{
    if (arg.has_value())
        s << *arg;
    else
        s << "<VALUELESS_OPTIONAL>";
    return s;
}
 
 
} // namespace seqan3