From 8aef14386fc403ee631f176abf0ec86af7dcd37b Mon Sep 17 00:00:00 2001 From: Michael Lutz Date: Sun, 17 May 2020 23:32:01 +0200 Subject: Add: Optional implementation of std::optional for pre-C++17 compilers. Sourced from https://github.com/akrzemi1/Optional, Boost Software License, Version 1.0. --- src/3rdparty/optional/ottd_optional.h | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 src/3rdparty/optional/ottd_optional.h (limited to 'src/3rdparty/optional/ottd_optional.h') diff --git a/src/3rdparty/optional/ottd_optional.h b/src/3rdparty/optional/ottd_optional.h new file mode 100644 index 000000000..19b44c505 --- /dev/null +++ b/src/3rdparty/optional/ottd_optional.h @@ -0,0 +1,33 @@ +/* + * This file is part of OpenTTD. + * OpenTTD 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, version 2. + * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see . + */ + +/** @file ottd_optional.h Header to select between native. */ + +#ifndef OTTD_OPTIONAL_H +#define OTTD_OPTIONAL_H + +#if defined(__has_include) +# if __has_include() +# include +# endif +#endif + +#if (__cplusplus >= 201703L) || (defined(__cpp_lib_optional) && __cpp_lib_optional >= 201606L) + +/* Native std::optional. */ +#include +namespace opt = std; + +#else + +/* No std::optional, use local copy instead. */ +#include "optional.hpp" +namespace opt = std::experimental; + +#endif + +#endif /* OTTD_OPTIONAL_H */ -- cgit v1.2.3-70-g09d2