boolean.hpp

/*
 * Copyright (c) 2024 The RefValue Project
 *
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 * of this software and associated documentation files (the "Software"), to deal
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 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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 * THE SOFTWARE.
 */
 
#pragma once
 
#include <concepts>
#include <type_traits>
 
namespace essence {
    template <typename T>
    constexpr bool convert_to_boolean(const T& value) noexcept {
        if constexpr (std::is_null_pointer_v<std::decay_t<T>>) {
            return false;
        } else if constexpr (std::convertible_to<T, bool> || std::constructible_from<bool, T>) {
            return bool{value};
        } else {
            return true;
        }
    }
} // namespace essence