On Apr 8, 12:02   
> Not at the moment! (And there's something i'm working on in which
> I would quite like to have a recursive map/collect.)
>
> But I have been thinking about it since Roger Pack's posthttp://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/360275
> and the subsequent posts on that.
>
> One thing that's been worrying me is the possibility of, for example,
> recursive arrays or hashes, or sets of arrays and or hashes
> which form a "loop". Do you have anything in #recursive to detect that?

I wasn't planning on it. I figure Ruby's internals might catch it on
their own and if not then I'd just post a warning in the docs not to
use on such objects. You'll get a stack overflow error regardless.
But, hey, if someone has a good solution for that too then all the
better, but I fear it would be very inefficient to ensure no "loops",
but maybe I am wrong about that.