Sprout/sprout/functional/polymorphic/cond.hpp

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2012-06-21 04:34:26 +00:00
#ifndef SPROUT_FUNCTIONAL_POLYMORPHIC_COND_HPP
#define SPROUT_FUNCTIONAL_POLYMORPHIC_COND_HPP
#include <utility>
#include <sprout/config.hpp>
#include <sprout/utility/forward.hpp>
namespace sprout {
//
// cond_t
// cond_
//
struct cond_t {
public:
template<typename T, typename U, typename V>
SPROUT_CONSTEXPR decltype(std::declval<T>() ? std::declval<U>() : std::declval<V>())
operator()(T&& x, U&& y, V&& z)
const SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(std::declval<T>() ? std::declval<U>() : std::declval<V>()))
{
return sprout::forward<T>(x) ? sprout::forward<U>(y) : sprout::forward<V>(z);
}
};
namespace {
SPROUT_STATIC_CONSTEXPR sprout::cond_t cond_{};
} // anonymous-namespace
} // namespace sprout
#endif // #ifndef SPROUT_FUNCTIONAL_POLYMORPHIC_COND_HPP