load.hpp

// SPDX-FileCopyrightText: 2006-2025 Knut Reinert & Freie Universität Berlin
// SPDX-FileCopyrightText: 2016-2025 Knut Reinert & MPI für molekulare Genetik
// SPDX-License-Identifier: CC0-1.0
 
#include <fstream>
#include <vector>
 
#include <seqan3/core/debug_stream.hpp>
#include <seqan3/test/tmp_directory.hpp>

#include <cereal/archives/binary.hpp> // includes the cereal::BinaryInputArchive and cereal::BinaryOutputArchive
#include <cereal/types/vector.hpp> // includes cerealisation support for std::vector
 
// Written for std::vector, other types also work.
void load(std::vector<int16_t> & data, std::filesystem::path const & tmp_file)
{
    std::ifstream is(tmp_file, std::ios::binary); // Where input can be found.
    cereal::BinaryInputArchive archive(is);       // Create an input archive from the input stream.
    archive(data);                                // Load data.
}
 
// Written for std::vector, other types also work.
void store(std::vector<int16_t> const & data, std::filesystem::path const & tmp_file)
{
    std::ofstream os(tmp_file, std::ios::binary); // Where output should be stored.
    cereal::BinaryOutputArchive archive(os);      // Create an output archive from the output stream.
    archive(data);                                // Store data.
}
 
int main()
{
    // The following example is for a std::vector but any seqan3 data structure that is documented as serialisable
    // could be used, e.g. seqan3::fm_index.
    seqan3::test::tmp_directory tmp{};
    auto tmp_file = tmp.path() / "data.out"; // This is a temporary file name, use any other filename.
 
    std::vector<int16_t> vec{1, 2, 3, 4};
    store(vec, tmp_file); // Calls store on a std::vector.
    // This vector is needed to load the information into it.
    std::vector<int16_t> vec2;
    load(vec2, tmp_file); // Calls load on a std::vector.
 
    seqan3::debug_stream << vec2 << '\n'; // Prints [1,2,3,4].
 
    return 0;
}