repeat_n.hpp

Go to the documentation of this file.

// -----------------------------------------------------------------------------------------------------
// Copyright (c) 2022 deCODE Genetics
// Copyright (c) 2006-2020, Knut Reinert & Freie Universität Berlin
// Copyright (c) 2016-2020, Knut Reinert & MPI für molekulare Genetik
// This file may be used, modified and/or redistributed under the terms of the 3-clause BSD-License
// shipped with this file and also available at: https://github.com/biocpp/biocpp-core/blob/main/LICENSE.md
// -----------------------------------------------------------------------------------------------------
 
#pragma once
 
#include <concepts>
 
#include <bio/ranges/views/repeat.hpp>
#include <bio/ranges/views/take_exactly.hpp>
 
namespace bio::ranges::detail
{
 
struct repeat_n_fn
{
    template <typename value_t>
    constexpr auto operator()(value_t && value, size_t const count) const
    {
        static_assert(std::constructible_from<std::remove_cvref_t<value_t>, value_t>,
                      "The value passed to repeat_n must be (1) an lvalue and its type copy constructible; or "
                      "(2) an rvalue and its type move constructible.");
 
        return views::repeat(std::forward<value_t>(value)) | views::take_exactly(count);
    }
};
 
} // namespace bio::ranges::detail
 
namespace bio::ranges::views
{
 
inline constexpr auto repeat_n = detail::repeat_n_fn{};
 
} // namespace bio::ranges::views