Chris Rebert <c...@rebertia.com> writes: > It's a well-known problem due to the intricacies of Python's scoping > rules.
Actually, it is not specific to Python's scoping rules (which mandate local, then module-level, then built-in name lookup). The root of the surprise is, as you correctly point out, the fact that the variable's "cell" is shared by all iterations through the loop. Taking that into account, it logically follows that all enclosed functions end up reading the same value. This is not endemic to Python, the exact same surprise is present in Common Lisp, a language with long tradition of closures and otherwise radically different scoping rules. * (setq l (loop for i from 1 to 10 collect (lambda () i))) * (mapcar #'funcall l) (11 11 11 11 11 11 11 11 11 11) -- http://mail.python.org/mailman/listinfo/python-list
