I do not see the problem with newtype, but rather with fromOneToFive and toList. As soon as you use them, you are left with an Int and a List. So why complain s

I do not see the problem with newtype, but rather with fromOneToFive and toList. As soon as you use them, you are left with an Int and a List. So why complain safety is lost when it has been intentionally lost? If the compiler does not provide safe ways of working of newtype's, the programmer indeed has to provide them in the form of methods, basically just as shown in the article.