is_constant_evaluated.hpp

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// SPDX-License-Identifier: BSL-1.0
// SPDX-FileCopyrightText: Copyright (C) 2019 Tobias Hienzsch
 
#ifndef TETL_TYPE_TRAITS_IS_CONSTANT_EVALUATED_HPP
#define TETL_TYPE_TRAITS_IS_CONSTANT_EVALUATED_HPP
 
#include <etl/_config/all.hpp>
 
namespace etl {
 
/// \brief Detects whether the function call occurs within a constant-evaluated
/// context. Returns true if the evaluation of the call occurs within the
/// evaluation of an expression or conversion that is manifestly
/// constant-evaluated; otherwise returns false.
///
/// https://en.cppreference.com/w/cpp/types/is_constant_evaluated
[[nodiscard]] constexpr auto is_constant_evaluated() noexcept -> bool
{
#if __has_builtin(__builtin_is_constant_evaluated)
    return __builtin_is_constant_evaluated();
#else
    return false;
#endif
}
 
} // namespace etl
 
#endif // TETL_TYPE_TRAITS_IS_CONSTANT_EVALUATED_HPP