I think the idea of a standard iterator interface is good, it will allow standard implementations of Map, Filter, and other convenient functional helpers. But

I think the idea of a standard iterator interface is good, it will allow standard implementations of Map, Filter, and other convenient functional helpers. But I have mixed feelings on the overloading of the "for x := range" syntax. One of the things I like about go is that it's easy to dive into a new code base and understand what's going on. Overloading the range operator means to understand a for loop I need to jump around to understand the iterator implementation. It's already pretty easy to loop over an iterator, e.g. for { x, ok := it.Next() if !ok { break } ... } I'm not convinced that overloading range is worth it. But on the other hand, I'm sure I would get used to it fairly quickly