Mailman 3 March 2013 - docs

[issue12174] Multiprocessing logging levels unclear
by JJeffries Oct. 22, 2020

Oct. 22, 2020

New submission from JJeffries <jamesjeffries1(a)gmail.com>: It is unclear without reference to the logging module where the multiprocessing logging levels fit in the normal logging provided by the logging module, even though it says above the table "The table below illustrates where theses fit in the normal level hierarchy. +----------------+----------------+ | Level | Numeric value | +================+================+ | ``SUBWARNING`` | 25 | +----------------+---… [View More]

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[issue13047] imp.find_module("") and imp.find_module(".")
by Arfrever Frehtes Taifersar Arahesis Oct. 22, 2020

Oct. 22, 2020

New submission from Arfrever Frehtes Taifersar Arahesis <Arfrever.FTA(a)GMail.Com>: It's undocumented that imp.find_module("") and imp.find_module(".") try to find __init__.py. There is also a small difference in behavior between them. sys.path by default contains "" as the first element, which is sufficient for imp.find_module("."), but not for imp.find_module(""): $ mkdir /tmp/imp_tests $ cd /tmp/imp_tests $ touch __init__.py $ python3.3 -c 'import imp, sys; print(repr(sys.path[0])); … [View More]

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[issue14979] pdb: Link to source
by anatoly techtonik Oct. 22, 2020

Oct. 22, 2020

New submission from anatoly techtonik <techtonik(a)gmail.com>: http://docs.python.org/library/pdb.html#pdb.Pdb Documentation for pdb says: "The debugger is extensible — it is actually defined as the class Pdb. This is currently undocumented but easily understood by reading the source." There should a link to the source. ---------- assignee: docs@python components: Documentation, Library (Lib) messages: 162074 nosy: docs@python, techtonik priority: normal severity: normal status: open … [View More]

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[issue13828] Further improve casefold documentation
by Jim Jewett Aug. 24, 2020

Aug. 24, 2020

New submission from Jim Jewett <jimjjewett(a)gmail.com>: > http://hg.python.org/cpython/rev/0b5ce36a7a24 > changeset: 74515:0b5ce36a7a24 > + Casefolding is similar to lowercasing but more aggressive because it is > + intended to remove all case distinctions in a string. For example, the German > + lowercase letter ``'ß'`` is equivalent to ``"ss"``. Since it is already > + lowercase, :meth:`lower` would do nothing to ``'ß'``; :meth:`… [View More]

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[issue17589] Make documentation about macros in C API explicit about rvalue vs statement
by Larry Hastings June 25, 2020

June 25, 2020

New submission from Larry Hastings: CPython API "functions" implemented as macros can expand into either rvalues or statements. Most expand into statements (often using the do {} while (0) syntactic sugar trick), but occasionally they're legal as rvalues. As of this writing Py_INCREF works as an rvalue. But discussion on another tracker issue (#17206) proposes changing the implementation in such a way that it will only be usable as a statement. Although it's mildly unlikely, it's certainly … [View More]

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[issue17110] sys.argv docs should explaining how to handle encoding issues
by Nick Coghlan June 18, 2020

June 18, 2020

New submission from Nick Coghlan: The sys.argv docs [1] currently contain no mention of the fact that they are Unicode strings decoded from bytes provided by the OS. They also don't explain how to correct a decoding error by reversing Python's implicit conversion and redoing it based on the application's knowledge of the correct encoding, as described at [2] [1] http://docs.python.org/3/library/sys#sys.argv [2] http://stackoverflow.com/questions/6981594/sys-argv-as-bytes-in-python-3k/ ------… [View More]

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[issue16891] Fix docs about module search order
by Dmitry Mugtasimov May 31, 2020

May 31, 2020

New submission from Dmitry Mugtasimov: http://docs.python.org/2/tutorial/modules.html should be rewritten. AS IS 6.1.2. The Module Search Path When a module named spam is imported, the interpreter first searches for a built-in module with that name. If not found, it then searches for a file named spam.py in a list of directories given by the variable sys.path. sys.path is initialized from these locations: TO BE 6.1.2. The Module Search Path When a module named spam is imported, the … [View More]interpreter first searches for a built-in module with that name. If not found, it looks in the containing package (the package of which the current module is a submodule). If not found, it then searches for a file named spam.py in a list of directories given by the variable sys.path. sys.path is initialized from these locations: ------ Note that now "6.1.2. The Module Search Path" and "6.4.2. Intra-package References" are contradictary since in 6.4.2 it is said: "In fact, such references are so common that the import statement first looks in the containing package before looking in the standard module search path.", but this is not reflected in 6.1.2. ------ EXAMPLE (for more information see http://stackoverflow.com/questions/14183541/why-python-finds-module-instead… ): /home/dmugtasimov/tmp/name-res3/xyz __init__.py a.py b.py t.py xyz.py Files init.py, b.py and xyz.py are empty File a.py: import os, sys ROOT_DIRECTORY = os.path.abspath(os.path.join(os.path.dirname(__file__), '..')) if not sys.path or ROOT_DIRECTORY not in sys.path: print 'sys.path is modified in a.py' sys.path.insert(0, ROOT_DIRECTORY) else: print 'sys.path is NOT modified in a.py' print 'sys.path:', sys.path print 'BEFORE import xyz.b' import xyz.b print 'AFTER import xyz.b' File t.py: import os, sys ROOT_DIRECTORY = os.path.abspath(os.path.join(os.path.dirname(__file__), '..')) if not sys.path or ROOT_DIRECTORY not in sys.path: print 'sys.path is modified in t.py' sys.path.insert(0, ROOT_DIRECTORY) else: print 'sys.path is NOT modified in t.py' import xyz.a Run: python a.py Output: sys.path is modified in a.py sys.path: ['/home/dmugtasimov/tmp/name-res3', '/home/dmugtasimov/tmp/name-res3/xyz', '/usr/local/lib/python2.7/dist-packages/tornado-2.3-py2.7.egg', '/home/dmugtasimov/tmp/name-res3/xyz', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-linux2', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', '/usr/local/lib/python2.7/dist-packages/setuptools-0.6c11-py2.7.egg-info', '/usr/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages/PIL', '/usr/lib/python2.7/dist-packages/gst-0.10', '/usr/lib/python2.7/dist-packages/gtk-2.0', '/usr/lib/python2.7/dist-packages/ubuntu-sso-client'] BEFORE import xyz.b AFTER import xyz.b Run: python -vv a.py Output: import xyz # directory /home/dmugtasimov/tmp/name-res3/xyz # trying /home/dmugtasimov/tmp/name-res3/xyz/__init__.so # trying /home/dmugtasimov/tmp/name-res3/xyz/__init__module.so # trying /home/dmugtasimov/tmp/name-res3/xyz/__init__.py # /home/dmugtasimov/tmp/name-res3/xyz/__init__.pyc matches /home/dmugtasimov/tmp/name-res3/xyz/__init__.py import xyz # precompiled from /home/dmugtasimov/tmp/name-res3/xyz/__init__.pyc # trying /home/dmugtasimov/tmp/name-res3/xyz/b.so # trying /home/dmugtasimov/tmp/name-res3/xyz/bmodule.so # trying /home/dmugtasimov/tmp/name-res3/xyz/b.py # /home/dmugtasimov/tmp/name-res3/xyz/b.pyc matches /home/dmugtasimov/tmp/name-res3/xyz/b.py import xyz.b # precompiled from /home/dmugtasimov/tmp/name-res3/xyz/b.pyc Run: python t.py Output: sys.path is modified in t.py sys.path is NOT modified in a.py sys.path: ['/home/dmugtasimov/tmp/name-res3', '/home/dmugtasimov/tmp/name-res3/xyz', '/usr/local/lib/python2.7/dist-packages/tornado-2.3-py2.7.egg', '/home/dmugtasimov/tmp/name-res3/xyz', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-linux2', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', '/usr/local/lib/python2.7/dist-packages/setuptools-0.6c11-py2.7.egg-info', '/usr/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages/PIL', '/usr/lib/python2.7/dist-packages/gst-0.10', '/usr/lib/python2.7/dist-packages/gtk-2.0', '/usr/lib/python2.7/dist-packages/ubuntu-sso-client'] BEFORE import xyz.b Traceback (most recent call last): File "t.py", line 9, in <module> import xyz.a File "/home/dmugtasimov/tmp/name-res3/xyz/a.py", line 11, in <module> import xyz.b ImportError: No module named b Run: python -vv t.py Output: import xyz # directory /home/dmugtasimov/tmp/name-res3/xyz # trying /home/dmugtasimov/tmp/name-res3/xyz/__init__.so # trying /home/dmugtasimov/tmp/name-res3/xyz/__init__module.so # trying /home/dmugtasimov/tmp/name-res3/xyz/__init__.py # /home/dmugtasimov/tmp/name-res3/xyz/__init__.pyc matches /home/dmugtasimov/tmp/name-res3/xyz/__init__.py import xyz # precompiled from /home/dmugtasimov/tmp/name-res3/xyz/__init__.pyc # trying /home/dmugtasimov/tmp/name-res3/xyz/a.so # trying /home/dmugtasimov/tmp/name-res3/xyz/amodule.so # trying /home/dmugtasimov/tmp/name-res3/xyz/a.py # /home/dmugtasimov/tmp/name-res3/xyz/a.pyc matches /home/dmugtasimov/tmp/name-res3/xyz/a.py import xyz.a # precompiled from /home/dmugtasimov/tmp/name-res3/xyz/a.pyc # trying /home/dmugtasimov/tmp/name-res3/xyz/os.so # trying /home/dmugtasimov/tmp/name-res3/xyz/osmodule.so # trying /home/dmugtasimov/tmp/name-res3/xyz/os.py # trying /home/dmugtasimov/tmp/name-res3/xyz/os.pyc # trying /home/dmugtasimov/tmp/name-res3/xyz/sys.so # trying /home/dmugtasimov/tmp/name-res3/xyz/sysmodule.so # trying /home/dmugtasimov/tmp/name-res3/xyz/sys.py # trying /home/dmugtasimov/tmp/name-res3/xyz/sys.pyc # trying /home/dmugtasimov/tmp/name-res3/xyz/xyz.so # trying /home/dmugtasimov/tmp/name-res3/xyz/xyzmodule.so # trying /home/dmugtasimov/tmp/name-res3/xyz/xyz.py # /home/dmugtasimov/tmp/name-res3/xyz/xyz.pyc matches /home/dmugtasimov/tmp/name-res3/xyz/xyz.py import xyz.xyz # precompiled from /home/dmugtasimov/tmp/name-res3/xyz/xyz.pyc # clear[2] __file__ # clear[2] __package__ # clear[2] sys # clear[2] ROOT_DIRECTORY # clear[2] __name__ # clear[2] os sys.path is modified in t.py sys.path is NOT modified in a.py sys.path: ['/home/dmugtasimov/tmp/name-res3', '/home/dmugtasimov/tmp/name-res3/xyz', '/usr/local/lib/python2.7/dist-packages/tornado-2.3-py2.7.egg', '/home/dmugtasimov/tmp/name-res3/xyz', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-linux2', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', '/usr/local/lib/python2.7/dist-packages/setuptools-0.6c11-py2.7.egg-info', '/usr/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages/PIL', '/usr/lib/python2.7/dist-packages/gst-0.10', '/usr/lib/python2.7/dist-packages/gtk-2.0', '/usr/lib/python2.7/dist-packages/ubuntu-sso-client'] BEFORE import xyz.b Traceback (most recent call last): File "t.py", line 9, in <module> import xyz.a File "/home/dmugtasimov/tmp/name-res3/xyz/a.py", line 11, in <module> import xyz.b ImportError: No module named b As you see sys.path is the same for both cases: sys.path: ['/home/dmugtasimov/tmp/name-res3', '/home/dmugtasimov/tmp/name-res3/xyz', '/usr/local/lib/python2.7/dist-packages/tornado-2.3-py2.7.egg', '/home/dmugtasimov/tmp/name-res3/xyz', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-linux2', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', '/usr/local/lib/python2.7/dist-packages/setuptools-0.6c11-py2.7.egg-info', '/usr/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages/PIL', '/usr/lib/python2.7/dist-packages/gst-0.10', '/usr/lib/python2.7/dist-packages/gtk-2.0', '/usr/lib/python2.7/dist-packages/ubuntu-sso-client'] But the behaviour is different. For a.py python searches for package xyz first, and them for module b in it: import xyz # directory /home/dmugtasimov/tmp/name-res3/xyz # trying /home/dmugtasimov/tmp/name-res3/xyz/__init__.so # trying /home/dmugtasimov/tmp/name-res3/xyz/__init__module.so # trying /home/dmugtasimov/tmp/name-res3/xyz/__init__.py # /home/dmugtasimov/tmp/name-res3/xyz/__init__.pyc matches /home/dmugtasimov/tmp/name-res3/xyz/__init__.py import xyz # precompiled from /home/dmugtasimov/tmp/name-res3/xyz/__init__.pyc # trying /home/dmugtasimov/tmp/name-res3/xyz/b.so # trying /home/dmugtasimov/tmp/name-res3/xyz/bmodule.so # trying /home/dmugtasimov/tmp/name-res3/xyz/b.py # /home/dmugtasimov/tmp/name-res3/xyz/b.pyc matches /home/dmugtasimov/tmp/name-res3/xyz/b.py import xyz.b # precompiled from /home/dmugtasimov/tmp/name-res3/xyz/b.pyc In other words: Search PACKAGE xyz in directory sys.path[0] -> FOUND Search module b in PACKAGE xyz -> FOUND Continue execution For t.py it searches for moduel xyz in the same directory as a.py itself and then fails to find module b in module xyz: # trying /home/dmugtasimov/tmp/name-res3/xyz/xyz.so # trying /home/dmugtasimov/tmp/name-res3/xyz/xyzmodule.so # trying /home/dmugtasimov/tmp/name-res3/xyz/xyz.py # /home/dmugtasimov/tmp/name-res3/xyz/xyz.pyc matches /home/dmugtasimov/tmp/name-res3/xyz/xyz.py import xyz.xyz # precompiled from /home/dmugtasimov/tmp/name-res3/xyz/xyz.pyc In other words: Search MODULE xyz in directory in the same directory as a.py (or sys.path[1] ?) -> FOUND Search MODULE b in MODULE xyz -> NOT FOUND ImportError So it looks like if "import xyz.b" bahaves different depending on how a.py was initially loaded as a script or imported from another module. ---------- assignee: docs@python components: Documentation messages: 179321 nosy: dmugtasimov, docs@python priority: normal severity: normal status: open title: Fix docs about module search order type: behavior versions: Python 2.7 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue16891> _______________________________________ [View Less]

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[issue13649] termios.ICANON is not documented
by anatoly techtonik May 31, 2020

May 31, 2020

New submission from anatoly techtonik <techtonik(a)gmail.com>: http://docs.python.org/library/termios.html is missing documentation for ICANON flag used to put terminal to "raw" mode. It is also worth to place `termios` raw/canonical mode equivalent on `tty` pages, so that people porting C code to Python could understand the hidden magic. ---------- assignee: docs@python components: Documentation, IO, Library (Lib) messages: 150098 nosy: docs@python, techtonik priority: normal severity:… [View More]

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[issue16700] Document that bytes OS API can returns unusable results on Windows
by Serhiy Storchaka May 31, 2020

May 31, 2020

New submission from Serhiy Storchaka: Some OS functions which returns bytes (os.environb, os.getenvb(), os.getcwdb(), os.listdir(), os.readlink(), os.walk(), os.path.abspath(), os.path.expanduser(), os.path.expandvars(), os.path.realpath() and may be other) can return unusable result on Windows (see for example issue13247 and issue16656). The documentation should contains strong warnings about this. ---------- assignee: docs@python components: Documentation, Windows messages: 177613 nosy: … [View More]

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[issue9196] Improve docs for string interpolation "%s" re Unicode strings
by Craig McQueen May 31, 2020

May 31, 2020

New submission from Craig McQueen <python(a)craig.mcqueen.id.au>: I have just been trying to figure out how string interpolation works for "%s", when Unicode strings are involved. It seems it's a bit complicated, but the Python documentation doesn't really describe it. It just says %s "converts any Python object using str()". Here is what I have found (I think), and it could be worth improving the documentation of this somehow. Example 1: "%s" % test_object >From what I can … [View More]

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