msgpage C ++：使用MSGPACK_DEFINE发送原始指针

Question

I would like to send the following struct over msgpack.

struct MyStruct {
    std::string     name{""};
    int*            val{nullptr};

    MSGPACK_DEFINE( name, val );
};

Thus far in all of my projects, the only way I've streamed with msgpack is using MSGPACK_DEFINE, then writing the struct to msgpack::sbuffer (and sending it). the MSGPACK_DEFINE macro complains that that perhaps I missed the "->" so I'm guessing it doesn't detect that it's a pointer.

Smart pointers seem to work though:

struct MyStruct {
    std::string          name{""};
    std::shared_ptr<int> val{nullptr};

    MSGPACK_DEFINE( name, val );
};

The caveat is that the receiver on the other end needs val to be a raw pointer. I would like to do this without converting on the receiving side. Any ideas?

Answer 1

You failed to explain why you wish to do this. Pointers are never meaningful when serialized (otherwise it is in-process data and there is no need to serialize).

Just pass the value that the pointer points to. If you need to represent "a number or NULL", then pass a struct containing an integer and boolean.

struct NullableInt {
    int value{0};
    bool null{true};
};