Personally, I think that assuming that "bar" should be installed without any more hints from the user is a bit of a stretch; they asked to install "foo", not "bar", and it can't be installed. I don't know that aptitude should be trying to second-guess its command line here.
I do think that it would make sense for aptitude to print out a list of packages that C/P/R "foo". Daniel -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org