Can one create Sized Types in Scala?

Is it possible to create types like e.g. String(20) in scala?

The aim would be to have compiler checks for things like:

a: String(20) 
b: String(30)
a = b; // throws开发者_如何学编程 a compiler exception when no implicit conversion is available
b= a; // works just fine

Note: It doesn't need to be/named String

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Yes, it is possible, using Church Numerals encoding. Jim McBeath has a good series of blogs relating to that. Start here, but keep looking for other references on the Internet. He wasn't the only one to talk about it, nor was this his only post.

It isn't, however, very much practical.