New submission from Joshua Landau <joshua.landau...@gmail.com>: When setting defaults to keyword-only arguments in lambdas which are inside non-global scopes, cPython doesn't push the name to it's closure's co_freevars.
EXAMPLE: global_variable = None (lambda: (lambda *, keyword_only=global_variable: None))() Because the inner lambda hasn't told the outer lambda to put global_variable in co_freevars, it fails to create the default to keyword_only. This only happens if the inner function is a lambda and you are setting a keyword_only variable. It does not cause a crash if global_variable is local to the outer lambda, as the opcode LOAD_FAST is still created properly (as opposed to LOAD_NAME). It does not crash if global_variable is used elsewhere in the outer function as co_freevars will be updated with it, allowing LOAD_NAME to retrieve it. I've never done a bug here before and I'm unsure what to say, so please be nice and correct me if I'm doing it wrong. ---------- components: Interpreter Core messages: 147026 nosy: Joshua.Landau priority: normal severity: normal status: open title: Lambda keyword-only argument not updating co_freevars type: crash versions: Python 3.2 _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue13343> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
