[issue34431] Docs does not eval allows code object as argument
New submission from Jonathan Fine <jfine2358@gmail.com>: See https://docs.python.org/3.6/library/functions.html#eval This says the following won't happen. But it does. Python 3.6.2 (default, Jul 29 2017, 00:00:00) [GCC 4.8.4] on linux Type "help", "copyright", "credits" or "license" for more information.
def fn(): print(3); return 4 ... eval(fn.__code__) 3 4
Compare with https://docs.python.org/3.6/library/functions.html#exec Search for eval in title of open issues bring up related #22057 (The doc say all globals are copied on eval(), but only __builtins__ is copied) #25810 (Python 3 documentation for eval is incorrect) ---------- assignee: docs@python components: Documentation messages: 323716 nosy: docs@python, jfine2358 priority: normal severity: normal status: open title: Docs does not eval allows code object as argument versions: Python 2.7, Python 3.4, Python 3.5, Python 3.6, Python 3.7, Python 3.8 _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34431> _______________________________________
Berker Peksag <berker.peksag@gmail.com> added the comment: Thank you for your report. Quoting from https://docs.python.org/3.6/library/functions.html#eval This function can also be used to execute arbitrary code objects (such as those created by compile()). In this case pass a code object instead of a string. So, your example is already documented as a legal way of using the eval() function. I don't see anything wrong here. ---------- nosy: +berker.peksag resolution: -> not a bug status: open -> pending type: -> behavior versions: -Python 3.4, Python 3.5 _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34431> _______________________________________
Jonathan Fine <jfine2358@gmail.com> added the comment: Summary: There's my problem, and others. I'm willing to provide a patch, if supported. There's a gotcha here. I fell into it. The docs for eval state === eval(expression, globals=None, locals=None) The arguments are a string and optional globals and locals. === I read this and concluded, fairly I think, that I'm not allowed to pass in a code object [1]. So I didn't read any further. I'd already got the answer to my question. But I knew that exec would take a code object, so I had doubt, and did my little experiment. I'd prefer something more like exec, which says === This function supports dynamic execution of Python code. object must be either a string or a code object. === There are other problems, such as not agreeing with the help(eval) etc messages (and the still open #22057, #25810): === eval(source, globals=None, locals=None, /) Evaluate the given source in the context of globals and locals. The source may be a string representing a Python expression or a code object as returned by compile(). The globals must be a dictionary and locals can be any mapping, defaulting to the current globals and locals. If only globals is given, locals defaults to it. === exec(source, globals=None, locals=None, /) Execute the given source in the context of globals and locals. The source may be a string representing one or more Python statements or a code object as returned by compile(). The globals must be a dictionary and locals can be any mapping, defaulting to the current globals and locals. If only globals is given, locals defaults to it. === Finally, I'm willing to provide a patch, if supported. (I've not contributed to Python before.) [1] I'd just read the docs for exec, which is up-front about 'string or code'. ---------- status: pending -> open _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34431> _______________________________________
Berker Peksag <berker.peksag@gmail.com> added the comment: Ok, I think it would be a good idea to mention that the function accepts a code object in the first sentence. I'd be happy to review such PR. The eval() documentation is located at https://github.com/python/cpython/blob/master/Doc/library/functions.rst See https://devguide.python.org/ for more details about the contribution process. Note that you need to sign the CLA in order to contribute to Python: https://www.python.org/psf/contrib/contrib-form/ #22057 and #25810 are out of scope for this issue, so let's not discuss them here. ---------- resolution: not a bug -> stage: -> needs patch _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34431> _______________________________________
Jonathan Fine <jfine2358@gmail.com> added the comment: OK. I'll do as you say. I've just signed the CLA. ---------- _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34431> _______________________________________
Cheryl Sabella <cheryl.sabella@gmail.com> added the comment: Hi Jonathan, Did you have any additional questions about opening a pull request for these changes? Thanks! ---------- nosy: +cheryl.sabella _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34431> _______________________________________
Jonathan Fine <jfine2358@gmail.com> added the comment: This graceful reminder is most welcome. At present, it's not help I'm short of, but time. I've given myself a reminder, to spend time on this before the end of this month (January 2019). Once again, thank you for this reminder. This is something I want to do. It would be my first Python contribution. ---------- _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34431> _______________________________________
Change by Furkan Onder <furkanonder@protonmail.com>: ---------- keywords: +patch nosy: +furkanonder nosy_count: 4.0 -> 5.0 pull_requests: +19313 stage: needs patch -> patch review pull_request: https://github.com/python/cpython/pull/20000 _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34431> _______________________________________
Furkan Onder <furkanonder@protonmail.com> added the comment: Hi Jonathan, Are you still planning to work on the patch? ---------- _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34431> _______________________________________
participants (4)
-
Berker Peksag -
Cheryl Sabella
-
Furkan Onder
-
Jonathan Fine