ranges.hpp

Go to the documentation of this file.

/*
    Copyright (C) 2021 - 2025
    Part of the Battle for Wesnoth Project https://www.wesnoth.org/
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY.
 
    See the COPYING file for more details.
*/
 
#pragma once
 
#ifdef __cpp_lib_ranges
#include <ranges>
#else
#include <boost/range/adaptor/filtered.hpp>
#include <boost/range/adaptor/map.hpp>
#include <boost/range/adaptor/reversed.hpp>
#include <boost/range/adaptor/transformed.hpp>
#endif
 
#ifndef __cpp_lib_ranges_stride
#include <boost/range/adaptor/strided.hpp>
#endif
 
namespace utils::views
{
#ifdef __cpp_lib_ranges
 
using std::views::filter;
using std::views::keys;
using std::views::reverse;
using std::views::transform;
using std::views::values;
 
#else
 
constexpr auto filter    = boost::adaptors::filtered;
constexpr auto keys      = boost::adaptors::map_keys;
constexpr auto reverse   = boost::adaptors::reversed;
constexpr auto transform = boost::adaptors::transformed;
constexpr auto values    = boost::adaptors::map_values;
 
#endif
 
//
// Ranges introduced in C++23
//
 
#ifdef __cpp_lib_ranges_stride
using std::views::stride;
#else
constexpr auto stride = boost::adaptors::strided;
#endif
 
} // namespace utils::views