adelegate.h

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This is part of Alterlib - the free code collection under the MIT License
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Copyright (C) 2006-2023 Maxim L. Grishin  (altmer@arts-union.ru)

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#ifndef ADELEGATE_H
#define ADELEGATE_H

namespace alt {

    //For MSVC you need to use CXXFLAGS /vmg /vmm

    class delegateBase{};

    template<typename RT, typename... AT>
    class delegate
    {
    public:
        delegate(){object=nullptr;method=nullptr;defret=RT();}
        delegate(const delegate &val){object=val.object;method=val.method;defret=val.defret;}
        delegate& operator=(const delegate &val){object=val.object;method=val.method;defret=val.defret;return *this;}

        template<typename OT>
        delegate(OT *obj,RT (OT::*proc)(AT...))
        {
            object=static_cast<delegateBase*>(obj);
            method=static_cast<RT (delegateBase::*)(AT...)>(proc);
        }
        ~delegate(){}

        void setDefRet(RT val){defret=val;}
        RT operator()(AT... args)
        {
            if(!object)return defret;
            return (object->*method)(args...);
        }

        bool empty() { return !object; }

    private:
        delegateBase *object;
        RT (delegateBase::*method)(AT...);
        RT defret;
    };


    template<typename... AT>
    class delegateProc
    {
    public:
        delegateProc(){object=nullptr;method=nullptr;}
        delegateProc(const delegateProc &val){object=val.object;method=val.method;}
        delegateProc& operator=(const delegateProc &val){object=val.object;method=val.method;return *this;}

        template<typename OT>
        delegateProc(OT *obj,void (OT::*proc)(AT...))
        {
            object=static_cast<delegateBase*>(obj);
            method=static_cast<void (delegateBase::*)(AT...)>(proc);
        }
        ~delegateProc(){}

        void operator()(AT... args)
        {
            if(!object)return;
            (object->*method)(args...);
        }

        bool empty() { return !object; }

    private:
        delegateBase *object;
        void (delegateBase::*method)(AT...);
    };

} // namespace alt

#endif // ADELEGATE_H