Am 12.03.2015 um 22:20 schrieb Sean P. DeNigris <sean@clipperadams.com>:

On Mar 12, 2015, at 4:54 PM, Sven Van Caekenberghe-2 [via Smalltalk] <[hidden email]> wrote:
The scheme is not optional, it defines what (kind) the URL is. You are expecting behaviour such as in a browser's address bar. But there, there is context (you are expecting an HTTP URL).

I did see the defaultScheme: variant. I���m not saying we should necessarily assume HTTP. I���m just saying if someone gives us a string like 'www.hm.com��� (which I agree is incompletely defined), why set #segments and not #host? Even with scheme = nil, the following would be more useful:
'www.hm.com' asUrl host = 'www.hm.com'. 
'www.hm.com' asUrl segments = m') an OrderedCollection()

To me it is a discussion what is the real interpretation of ZnUrl. It behaves mostly like URI but the name implies URL. Without a colon you are in URI land. It is just a path. Starting with /, // or without slash determines the kind of path.
So www.hm.com ist perfectly valid path. Just create a file named www.hm.com on your filesystem and you can luckily reference it with that URI. Having a URI/URL object in mind there is nothing to assume. From a text block point of view that might be different. Text display in apps use something like linkify. There you scan the content for patterns like www.*.* or even *.*.* (matching domains for the last part) and if you find some you assume it to be a URL with the host you've found. But then you create the URLs out of that given context. 
Maybe you need another selector like asHttpUrl?
My concern is more that

'urn:foo:bar' asUrl

doesn't do what it should :)

Norbert