[Jtsummers]

> But in many more modern languages, a "new type" is something the equivalent of

You don't even need a modern language for that kind of thing, plenty of languages from a half century or so ago also let you do that. From Ada (40+ years old):

  type PrimaryColor is (Red, Green, Blue);

Or if you're content with a mere alias, C (50+ years old) for your first example:

  typedef char* MyNewType;

[jerf]

It is true that modern is strictly speaking not the criterion. But what I was referring to is that the languages that were popular in, say, the 90s, generally did have that degree of ceremony.

C has its own problem. First, typedef isn't a new type, just an alias. But C's problem isn't the ceremony so much as the global namespace. Declaring a new type was nominally easy, but it had to have a crappy name, and you paid for that crappy name on every single use, with every function built for it, and so forth. You couldn't afford to just declare a new "IP" type because who knows what that would conflict with. A new type spent a valuable resource in C, a namespace entry. Fortunately modern languages make namespaces cheap too.