You know, while C++ references are technically unsafe, there is TRegisteredRefWrapper<> [1]. It's a safe version of std::reference_wrapper. Which kind of acts like a reference. So, if you don't mind me using std::strings instead of doubles, your example could be rewritten like

    mse::mstd::vector<mse::TRegisteredObj<std::string>> data(10);
    data[0] = "some text";
    mse::TRegisteredRefWrapper<std::string> dangling = data[0];
    data.resize(100000);
    try {
    	std::string crashing = dangling;
    }
    catch (...) {
    	// expected exception (not a segfault)
    	int q = 3;
    }

Does that work for you? I'm not an expert on std::reference_wrapper, so I'm not sure when it can and cannot substitute for a reference. (Btw, if it's a little verbose for you, there are shorter aliases available. Just search for "shorter aliases" in the header files.)

[1] https://github.com/duneroadrunner/SaferCPlusPlus#tregistered...