Hm. Right. I was going by the man page linked at cut. It says, "selected input is written in the same order that it is read." I took that to mean that arbitrary order is supported and respected. What else could it mean? But I don't see any explicit mention of non-increasing order. And it does explicitly state that each "selected input... is written exactly once." I find that either vague or redundant. What is a "selected input"? If "2" occurs in the spec twice, doesn't that make the second element a selected input twice, both of which are to be written exactly once? In any case, my perl version is at least as general, if not more so, than the cut version. :-)

Obviously there are other things cut can do which I have not (yet) implemented here.