That's what I would have thought, but it appeared to work. Though it may only have worked because of your second observation. And given that, I will repeat my desire for the destructive! custom. I like it because it doesn't interfere with any name (e.g. how alist could be association list or the "is the object a list?" predicate [though that's a bad example, you get the idea]), it has seen use in multiple languages, and it pretty clearly says what it means (assuming you want to encourage functional programming, as I think we do).
I suggest running a poll on this - of course, pg probably won't care either way, but we can integrate his code into Anarki next time he bothers to release an update, ne?
I think this convention is good; I'm just somewhat concerned with the fact that foo!bar is plenty overloaded.
edit: IIRC this has been suggested a few times before already, so I think there'll be good support for this - but it means we will then have to formally standardize the ssyntaxes too.
