I think it's a perfectly sane thing to want. In Common Lisp, for example, there are functions analogous to Perl's map that accumulate a return list (e.g. mapcar, and others that don't (e.g. mapc), plus the all-encompassing Lisp map that allows one to specify what kind of sequence one wants returned (e.g. list, vector, string) or none at all. It's nice to have all that available when you don't want to write an explicit loop.