func.h

 
#pragma once
 
#include "defines.h"
#include <functional>
#include <tuple>
#include <utility>
#include "system/multicast_delegate.h"
 
namespace System
{
namespace Detail
{
 
    template <typename Reordered, typename ...FuncArgs> struct FuncArgsReorderer;
 
    template <typename ...ReorderedArgs, typename FirstArg, typename ...OtherArgs>
    struct FuncArgsReorderer<void(ReorderedArgs...), FirstArg, OtherArgs...>
        : FuncArgsReorderer<void(ReorderedArgs..., FirstArg), OtherArgs...>
    {};
 
    template <typename ...ReorderedArgs, typename ReturnType>
    struct FuncArgsReorderer<void(ReorderedArgs...), ReturnType>
    {
        using type = ReturnType(ReorderedArgs...);
    };
 
} // namespace Detail
 
template<typename... Args>
class Func : public MulticastDelegate<typename ::System::Detail::FuncArgsReorderer<void(), Args...>::type>
{
    // There's no way to avoid using external template argument parser class as argument pack must be the last template argument, and in .Net Func arguments preceded the return value.
    // Also, there's no way to just alias MulticastDelegate, as this way deducing Func arguments doesn't work, and we have LINQ tests where it should.
public:
    Func()
        : MulticastDelegate<typename ::System::Detail::FuncArgsReorderer<void(), Args...>::type>()
    {}
    template <typename T>
    Func(T &&arg)
        : MulticastDelegate<typename ::System::Detail::FuncArgsReorderer<void(), Args...>::type>(arg)
    {}
    Func(const Func &func)
        : MulticastDelegate<typename ::System::Detail::FuncArgsReorderer<void(), Args...>::type>(func)
    {}
    Func(Func &&func) noexcept
        : MulticastDelegate<typename ::System::Detail::FuncArgsReorderer<void(), Args...>::type>(std::move(func))
    {}
    ~Func()
    {}
 
    Func& operator = (const Func &other)
    {
        MulticastDelegate<typename ::System::Detail::FuncArgsReorderer<void(), Args...>::type>::operator = (other);
        return *this;
    }
    Func& operator = (Func &&other) noexcept
    {
        MulticastDelegate<typename ::System::Detail::FuncArgsReorderer<void(), Args...>::type>::operator = (std::move(other));
        return *this;
    }
};
 
} // namespace System