I don't really understand why you would want this other than to trick yourself into thinking you are writing java. (I already find it really annoying when people port their Javaisms to C++.)
Yes, actually, I don't think it's controversial to say that Java did more to popularize immutable strings than any of the languages you're thinking of. And when people get CS degrees completely centered around Java, bring this kind of "feature" and others to C++, they end up churning out what looks a lot like pretend-Java.
Back then when I graduated (1999), at least in Portugal there were lots and lots of languages to use for assignments, during the degree (5 years long).
