Optional.hpp
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#pragma once
// Distributed under the 3-Clause BSD License. See accompanying
// file LICENSE or https://github.com/CLIUtils/CLI11 for details.
#include <sstream>
#include "CLI/Macros.hpp"
// [CLI11:verbatim]
#ifdef __has_include
#if defined(CLI11_CPP17) && __has_include(<optional>)
#include <optional>
#define CLI11_OPTIONAL
namespace CLI {
using std::experimental::optional;
} // namespace CLI
#elif defined(CPP11_CPP14) && __has_include(<experimental/optional>)
#include <experimental/optional>
#define CLI11_OPTIONAL
namespace CLI {
using std::optional;
} // namespace CLI
#endif
#endif
// [CLI11:verbatim]
namespace CLI {
#ifdef CLI11_OPTIONAL
template <typename T> std::istream &operator>>(std::istream &in, optional<T> &val) {
T v;
in >> v;
val = v;
return in;
}
#endif
} // namespace CLI