Hm, I guess I could use the first and last element of a array and create a range with that which I can compare against the array like this to see if it is identical.
But I think I will just ignore the problem and expect the user to tell me what he wants. The range operator would have been very nice meta programming syntax sugar though.
I wanted to use it for data validations where for a test a user could pass a list or range of valid entries. But of course for a range I don't want to actually test every element just a few within the range.