properties.cpp

template<typename T, T (*Get_F)(T *), void (*Set_F)(T *, T)>
class Property {
private:
    T field_;

public:
    explicit Property(T value)
    { this->field_ = value; }

    [[nodiscard]]
    T get() const
    { return Get_F(&(this->field_)); }

    void set(T value) const
    { Set_F((T *)(&(this->field_)), value); }

    Property<T, Get_F, Set_F> &operator =(T value)
    {
        this->set(value);
        return *this;
    }

    operator T()
    { return this->field_; }
};

template<typename T, T (*Get_F)(T *) = [](T *field) {
    return *field;
}, void (*Set_F)(T *, T) = [](T *field, T value) {
    *field = value;
}>
using property = class Property<T, Get_F, Set_F>;

int main()
{
    puts("Start");
    auto prop = property<int,
    [](int *i) {
        printf("%d\n", *i);
        return *i;
    },
    [](int *ptr, int i) {
        printf("%d, %d\n", *ptr, i);
        *ptr = i;
    }>(64);

    prop = 56;

    putchar(prop);

    return 0;
}

error:

FAILED: CMakeFiles/OoPenis.dir/main.cpp.o 
/usr/local/Cellar/gcc/11.2.0_3/bin/g++-11   -g -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk -mmacosx-version-min=12.2 -std=gnu++23 -MD -MT CMakeFiles/OoPenis.dir/main.cpp.o -MF CMakeFiles/OoPenis.dir/main.cpp.o.d -o CMakeFiles/OoPenis.dir/main.cpp.o -c /Users/Frityet/Documents/OoPenis/main.cpp
/Users/Frityet/Documents/OoPenis/main.cpp: In function 'int main()':
/Users/Frityet/Documents/OoPenis/main.cpp:150:6: error: 'main()::<lambda(int*)>::_FUN' is not a valid template argument for type 'int (*)(int*)' because 'static constexpr int main()::<lambda(int*)>::_FUN(int*)' has no linkage
  150 |     }>(64);
      |      ^
/Users/Frityet/Documents/OoPenis/main.cpp:150:6: error: 'main()::<lambda(int*, int)>::_FUN' is not a valid template argument for type 'void (*)(int*, int)' because 'static constexpr void main()::<lambda(int*, int)>::_FUN(int*, int)' has no linkage
ninja: build stopped: subcommand failed.