cppmp/include/cppmp/core/types.h

#pragma once

#include <cstddef>
#include <type_traits>

#include <cppmp/config.h>

namespace cppmp
{

    /**
     * @brief Evaluates to void.
     */
    template<typename...>
    using void_t = void;

    /**
     * @brief Store a single type.
     */
    template<typename X>
    struct type_t
        { };

    #ifdef cppmp_supports_variable_templates
    template<typename X>
    constexpr decltype(auto) type_v = type_t<X> { };
    #endif

    /**
     * @brief Simple type list.
     */
    template<typename...>
    struct list
        { };

    /**
     * @brief Inherit from all passed types.
     */
    template<typename... T>
    struct inherit
        : public T...
        { };

    /**
     * @brief Type to wrap constant values at compile time.
     */
    template<typename T, T t>
    struct integral_constant
        : public std::integral_constant<T, t>
        { };

    /**
     * @brief Boolean constant type.
     */
    template<bool B>
    struct bool_t
        : public integral_constant<bool, B>
        { };

    /**
     * @brief True boolean constant type.
     */
    struct true_t
        : public bool_t<true>
        { };

    /**
     * @brief False boolean constant type.
     */
    struct false_t
        : public bool_t<false>
        { };

    /**
     * @brief Size contant type.
     */
    template<size_t S>
    struct size_t
        : public integral_constant<std::size_t, S>
        { };

    /**
     * @brief Zero zize constant type.
     */
    struct zero_t
        : public size_t<0>
        { };

}