C++20就要来了，综合模块和概念正式特性的一个例子_c++20模块例子

// tooling.cpp
export module cxx.fuck.u; // Exposed to consumers.
import :details; // Consumers cannot import this module, internal only.
 
export namespace tooling
{
    class axxhole
    {
    public:
        axxhole() = default;
 
        inline operator std::string() { return "pretty"; }
 
        void feed()
        {
            details::feed_shit_impl(*this);
        }
};
}
 
 
// tooling_details.cpp
module cxx.fuck.u:details; // A module partition, for internal use only.
import std.core;
 
export namespace tooling::details
{
    template<typename T>
    concept CastableToString = requires(T t)
    {
        { t }->std::string;
    };
 
    template<typename TTarget>
    void feed_shit_impl(TTarget&& target) requires CastableToString<TTarget>
    {
        auto name = static_cast<std::string>(std::forward<TTarget>(target));
        std::cout << "Feeding " << name << "... Delicious!" << std::endl;
    }
}
 
// Consumers
import cxx.fuck.u;
 
int main()
{
    tooling::axxhole payload;
    payload.feed();
}