[issue8824] Improve documentation of exec
New submission from Terry J. Reedy <tjreedy@udel.edu>: This doc improvement suggestion is inspired by #991196 (and subsequent duplicates) and the current discussion on py-dev in the thread 'variable name resolution in exec is incorrect' (which is not a correct claim). I believe there is consensus that the doc for exec needs improving. My suggestion (which others may amend) is that the following paragraph (from the 3.x builtin functions exec entry) "In all cases, if the optional parts are omitted, the code is executed in the current scope. If only globals is provided, it must be a dictionary, which will be used for both the global and the local variables. If globals and locals are given, they are used for the global and local variables, respectively. If provided, locals can be any mapping object." have these two sentences added: "If only globals is provided or if onedict is provided as both globals and locals, the code is executed in a new top-level scope. If different objects are given as globals and locals, the code is executed as if it were in a class statement in a new top-level scope." ---------- assignee: docs@python components: Documentation messages: 106552 nosy: docs@python, tjreedy priority: normal severity: normal status: open title: Improve documentation of exec versions: Python 2.6, Python 2.7, Python 3.1, Python 3.2 _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Terry J. Reedy <tjreedy@udel.edu> added the comment: To be super-clear, consider adding one more sentence, something like "The result for code with def statements or lambda expressions may be different than it would be if the implied context were a function rather than a class." ---------- _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by Nick Coghlan <ncoghlan@gmail.com>: ---------- nosy: +ncoghlan _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Jordan Stadler <jordan.stadler@gmail.com> added the comment: I'm going to update the documentation to include the scope information. Should be done within a day. ---------- nosy: +jstadler _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by Jordan Stadler <jordan.stadler@gmail.com>: ---------- keywords: +patch Added file: http://bugs.python.org/file21960/exec_doc_touchup_2_x.patch _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by Jordan Stadler <jordan.stadler@gmail.com>: Added file: http://bugs.python.org/file21961/exec_doc_touchup_3_x.patch _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Jordan Stadler <jordan.stadler@gmail.com> added the comment: Patches for 2.x and 3.x documentation related to 'exec'. 2.x Provides more information about scopes when using additional expressions for 'exec'. 2.x documentation for 'exec' is found in reference/simple_stmts. 3.x Provides more information about scopes when using additional expressions for 'exec'. 3.x documentation for 'exec' is found in library/functions. ---------- _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by R. David Murray <rdmurray@bitdance.com>: ---------- nosy: +r.david.murray _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Ezio Melotti <ezio.melotti@gmail.com> added the comment: In 3.x exec is a function, so the reference to 'in' should be removed/updated. On 2.x it might be better to just use ``in`` instead of :keyword:`in`, because the latter probably links to the 'in' operator that checks for containment. ---------- nosy: +ezio.melotti stage: -> patch review versions: +Python 3.3 -Python 2.6 _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by Jordan Stadler <jordan.stadler@gmail.com>: Removed file: http://bugs.python.org/file21961/exec_doc_touchup_3_x.patch _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by Jordan Stadler <jordan.stadler@gmail.com>: Added file: http://bugs.python.org/file21981/exec_doc_touchup_3.x.patch _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by Jordan Stadler <jordan.stadler@gmail.com>: Added file: http://bugs.python.org/file21982/exec_doc_touchup_2.x.patch _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Jordan Stadler <jordan.stadler@gmail.com> added the comment: I've updated the 3.x patch, should be correct now. I also updated the 2.x patch to use ``in``. :keyword:`in` was used in an earlier part of the paragraph I modified, so I have changed both for consistency. This is the paragraph before modification: " In all cases, if the optional parts are omitted, the code is executed in the current scope. If only the first expression after :keyword:`in` is specified, it should be a dictionary, which will be used for both the global and the local variables. If two expressions are given, they are used for the global and local variables, respectively. If provided, *locals* can be any mapping object. " ---------- _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by Jordan Stadler <jordan.stadler@gmail.com>: Removed file: http://bugs.python.org/file21960/exec_doc_touchup_2_x.patch _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by Ezio Melotti <ezio.melotti@gmail.com>: ---------- nosy: +mark.dickinson type: -> enhancement versions: +Python 3.4 -Python 3.1 _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Mark Dickinson added the comment: Should this be closed as a duplicate of issue #13557? ---------- _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Changes by Mark Dickinson <dickinsm@gmail.com>: ---------- resolution: -> duplicate status: open -> closed superseder: -> exec of list comprehension fails on NameError _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Terry J. Reedy added the comment: I suggested more change here than I committed in #13557. I would like to think about the extra a bit more. The issue about def in exec just came up again on python-list, but I do not really like the third sentence I suggested. ---------- assignee: docs@python -> terry.reedy _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Mark Dickinson added the comment: Okay; sorry about that. Reopening. ---------- resolution: duplicate -> status: closed -> open _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue8824> _______________________________________
Terry J. Reedy <tjreedy@udel.edu> added the comment: I decided that the alternate addition in #13557 is enough. ---------- resolution: -> out of date stage: patch review -> resolved status: open -> closed versions: -Python 2.7 _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue8824> _______________________________________
participants (6)
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Ezio Melotti -
Jordan Stadler
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Mark Dickinson
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Nick Coghlan
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R. David Murray
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Terry J. Reedy