Mailman 3 October 2015 - Python-Dev

Not Deprecating Arbitrary Function Annotations
by Steve Wedig 06 Oct '15

06 Oct '15

Congratulations on the release of 3.5 and Pep 484. I've used Python professionally for 10 years and I believe type hints will make it easier to work with large codebases evolving over time. My only concern about Pep 484 is the discussion of whether or not to deprecate arbitrary function annotations. https://www.python.org/dev/peps/pep-0484/ I would like to request that arbitrary function annotations are not deprecated for three reasons: 1. Backwards Compatibility 2. Type Experimentation 3. Embedded Languages 1. Backwards Compatibility After reading Pep 3107 my team has made significant use of non-standard annotations. It would be a serious burden to be forced to port our annotations back to decorators. This would also make our codebase considerably less readable because function annotations are much more readable than input/output annotations relegated to decorators. https://www.python.org/dev/peps/pep-3107/ 2. Type Experimentation Arbitrary function annotations allow developers to experiment with potential type system improvements in real projects. Ideas can be validated before officially adding them to the language. This seems like an advantage that should be preserved. After all, Pep 484 says it was strongly inspired by MyPy, an existing project. http://mypy-lang.org/ 3. Embedded Languages Python's flexibility makes it an amazing language to embed other languages in. In this regard, Python 3's addition of arbitrary function annotations and class decorators complements Python 2's dynamic typing, function decorators, reflection, metaclasses, properties, magic methods, generators, and keyword arguments. Arbitrary function annotations are a crucial part of this toolkit, and this feature is not available in most other languages. For anyone interested in the utility and mechanics of embedded languages, I'd recommend Martin Fowler's book: Domain Specific Languages. http://www.amazon.com/Domain-Specific-Languages-Addison-Wesley-Signature-Se… So I agree with the course of action mentioned in Pep 484 that avoids runtime deprecation of arbitrary function annotation: "Another possible outcome would be that type hints will eventually become the default meaning for annotations, but that there will always remain an option to disable them." I would only add that there should be a way to disable type checking for an entire directory (recursively). This would be useful for codebases that have not been ported to standard annotations yet, and for codebases that will not be ported for the reasons listed above. Thanks for your consideration. Best, Steve

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3.4.4rc1, when?
by Terry Reedy 05 Oct '15

05 Oct '15

When, exactly, is 3.4.4c1 being branched off (which is when we should stop pushing non-critical patches)? The 3.4 PEP has no mention of 3.4.4 https://www.python.org/dev/peps/pep-0429/ -- Terry Jan Reedy

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VS 2010 compiler
by Chris Barker - NOAA Federal 03 Oct '15

03 Oct '15

As I understand it, the MS VS2010 compiler is required (or at least best practice) for compiling Python extensions for the python.org Windows builds of py 3.4 and ?[1] However, MS now makes it very hard (impossible?) to download VS2010 Express ( or Community, or whatever the free as in beer version is called). I realize that this is not python-dev's responsibility, but if there is any way to either document where it can be found, or put a bit of pressure on MS to make it available, as they have for VS2008 and py2.7, that would be great. Sorry to bug this list, I didn't know where else to reach out to. -Chris [1] it's actually prefer hard to find out which compiler version is used for which python version. And has been for years. Would a patch to the docs, probably here: https://docs.python.org/3.4/using/windows.html#compiling-python-on-windows Be considered?

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Summary of Python tracker Issues
by Python tracker 02 Oct '15

02 Oct '15

ACTIVITY SUMMARY (2015-09-25 - 2015-10-02) Python tracker at http://bugs.python.org/ To view or respond to any of the issues listed below, click on the issue. Do NOT respond to this message. Issues counts and deltas: open 5155 (+13) closed 31906 (+57) total 37061 (+70) Open issues with patches: 2286 Issues opened (48) ================== #25235: EmailMessage.add_attachment() creates parts with spurious MIME http://bugs.python.org/issue25235 opened by groner #25237: Add doc for tkinter commondialog.Dialog and subclasses http://bugs.python.org/issue25237 opened by terry.reedy #25238: Version added of context parameter for xmlrpc.client.ServerPro http://bugs.python.org/issue25238 opened by desbma #25239: HTMLParser handle_starttag replaces entity references in attri http://bugs.python.org/issue25239 opened by frogcoder #25240: Stack overflow in reprlib causes a core dump http://bugs.python.org/issue25240 opened by ceridwen #25242: Failed tests for Python 3.5.0 on shared virtual host http://bugs.python.org/issue25242 opened by Open Genomes #25243: decouple string-to-boolean logic from ConfigParser.getboolean http://bugs.python.org/issue25243 opened by jab #25244: Idle: refine right-click behavior http://bugs.python.org/issue25244 opened by terry.reedy #25246: Alternative algorithm for deque_remove() http://bugs.python.org/issue25246 opened by rhettinger #25247: Tkinter modules built successfully but removed because they co http://bugs.python.org/issue25247 opened by abrantesasf #25251: Unknown MS Compiler version 1900 http://bugs.python.org/issue25251 opened by Matt.Hickford #25252: Hard-coded line ending in asyncio.streams.StreamReader.readlin http://bugs.python.org/issue25252 opened by eric.smith #25254: Idle: debugger source line highlighting fails again http://bugs.python.org/issue25254 opened by terry.reedy #25256: Add sys.debug_build public variable to check if Python was com http://bugs.python.org/issue25256 opened by haypo #25257: In subject line email library inserts unwanted space after a t http://bugs.python.org/issue25257 opened by SegundoBob #25258: HtmlParser doesn't handle void element tags correctly http://bugs.python.org/issue25258 opened by Chenyun Yang #25259: readline macros can segfault Python http://bugs.python.org/issue25259 opened by gumnos #25263: test_tkinter fails randomly on the buildbots "AMD64 Windows10" http://bugs.python.org/issue25263 opened by haypo #25264: test_marshal always crashs on "AMD64 Windows10 2.7" buildbot http://bugs.python.org/issue25264 opened by haypo #25266: mako benchmark not working in Python 3.6 http://bugs.python.org/issue25266 opened by florin.papa #25268: Support pointing frozen modules to the corresponding source fi http://bugs.python.org/issue25268 opened by eric.snow #25269: Add method to detect if a string contains surrogates http://bugs.python.org/issue25269 opened by r.david.murray #25270: codecs.escape_encode systemerror on empty byte string http://bugs.python.org/issue25270 opened by reaperhulk #25272: asyncio tests are getting noisy http://bugs.python.org/issue25272 opened by gvanrossum #25274: sys.setrecursionlimit() must fail if the current recursion dep http://bugs.python.org/issue25274 opened by haypo #25275: Documentation v/s behaviour mismatch wrt integer literals cont http://bugs.python.org/issue25275 opened by shreevatsa #25276: Intermittent segfaults on PPC64 AIX 3.x http://bugs.python.org/issue25276 opened by haypo #25277: test_eintr hangs on randomly on "AMD64 FreeBSD 9.x 3.x" http://bugs.python.org/issue25277 opened by haypo #25278: Unexpected socket exception on SFTP 'STOR' command http://bugs.python.org/issue25278 opened by blanquier #25282: regex: Support for recursive patterns http://bugs.python.org/issue25282 opened by Sworddragon #25283: Make tm_gmtoff and tm_zone available on all platforms http://bugs.python.org/issue25283 opened by belopolsky #25285: regrtest: run tests in subprocesses with -j1 on buildbots http://bugs.python.org/issue25285 opened by haypo #25286: views are not sequences http://bugs.python.org/issue25286 opened by akira #25287: test_crypt fails on OpenBSD http://bugs.python.org/issue25287 opened by haypo #25289: test_strptime hangs sometimes on AMD64 Windows7 SP1 3.x buildb http://bugs.python.org/issue25289 opened by haypo #25290: csv.reader: minor docstring typo http://bugs.python.org/issue25290 opened by wasserverein #25291: better Exception message for certain task termination scenario http://bugs.python.org/issue25291 opened by ovex #25292: ssl socket gets into broken state when client exits during han http://bugs.python.org/issue25292 opened by ovex #25293: Hooking Thread/Process instantiation in concurrent.futures. http://bugs.python.org/issue25293 opened by Antony.Lee #25294: Absolute imports fail in some cases where relative imports wou http://bugs.python.org/issue25294 opened by Patrick Maupin #25295: functools.lru_cache raises KeyError http://bugs.python.org/issue25295 opened by Peter Brady #25296: Simple End-of-life guide covering all unsupported versions http://bugs.python.org/issue25296 opened by ncoghlan #25297: max_help_position is not works in argparse library http://bugs.python.org/issue25297 opened by morden2k #25298: Add lock and rlock weakref tests http://bugs.python.org/issue25298 opened by nirs #25299: TypeError: __init__() takes at least 4 arguments (4 given) http://bugs.python.org/issue25299 opened by A. Skrobov #25300: Enable Intel MPX (Memory protection Extensions) feature http://bugs.python.org/issue25300 opened by florin.papa #25301: Optimize UTF-8 decoder with error handlers http://bugs.python.org/issue25301 opened by haypo #25302: Memory Leaks with Address Sanitizer http://bugs.python.org/issue25302 opened by Matt Clarkson Most recent 15 issues with no replies (15) ========================================== #25302: Memory Leaks with Address Sanitizer http://bugs.python.org/issue25302 #25301: Optimize UTF-8 decoder with error handlers http://bugs.python.org/issue25301 #25298: Add lock and rlock weakref tests http://bugs.python.org/issue25298 #25294: Absolute imports fail in some cases where relative imports wou http://bugs.python.org/issue25294 #25293: Hooking Thread/Process instantiation in concurrent.futures. http://bugs.python.org/issue25293 #25292: ssl socket gets into broken state when client exits during han http://bugs.python.org/issue25292 #25290: csv.reader: minor docstring typo http://bugs.python.org/issue25290 #25287: test_crypt fails on OpenBSD http://bugs.python.org/issue25287 #25285: regrtest: run tests in subprocesses with -j1 on buildbots http://bugs.python.org/issue25285 #25283: Make tm_gmtoff and tm_zone available on all platforms http://bugs.python.org/issue25283 #25269: Add method to detect if a string contains surrogates http://bugs.python.org/issue25269 #25264: test_marshal always crashs on "AMD64 Windows10 2.7" buildbot http://bugs.python.org/issue25264 #25263: test_tkinter fails randomly on the buildbots "AMD64 Windows10" http://bugs.python.org/issue25263 #25246: Alternative algorithm for deque_remove() http://bugs.python.org/issue25246 #25244: Idle: refine right-click behavior http://bugs.python.org/issue25244 Most recent 15 issues waiting for review (15) ============================================= #25300: Enable Intel MPX (Memory protection Extensions) feature http://bugs.python.org/issue25300 #25298: Add lock and rlock weakref tests http://bugs.python.org/issue25298 #25287: test_crypt fails on OpenBSD http://bugs.python.org/issue25287 #25286: views are not sequences http://bugs.python.org/issue25286 #25285: regrtest: run tests in subprocesses with -j1 on buildbots http://bugs.python.org/issue25285 #25274: sys.setrecursionlimit() must fail if the current recursion dep http://bugs.python.org/issue25274 #25270: codecs.escape_encode systemerror on empty byte string http://bugs.python.org/issue25270 #25266: mako benchmark not working in Python 3.6 http://bugs.python.org/issue25266 #25256: Add sys.debug_build public variable to check if Python was com http://bugs.python.org/issue25256 #25251: Unknown MS Compiler version 1900 http://bugs.python.org/issue25251 #25246: Alternative algorithm for deque_remove() http://bugs.python.org/issue25246 #25235: EmailMessage.add_attachment() creates parts with spurious MIME http://bugs.python.org/issue25235 #25232: CGIRequestHandler behave incorrectly with query component cons http://bugs.python.org/issue25232 #25229: distutils doesn't add "-Wl," prefix to "-R" on Linux if the C http://bugs.python.org/issue25229 #25228: Regression in cookie parsing with brackets and quotes http://bugs.python.org/issue25228 Top 10 most discussed issues (10) ================================= #25220: Enhance and refactor test.regrtest (convert regrtest.py to a p http://bugs.python.org/issue25220 21 msgs #25274: sys.setrecursionlimit() must fail if the current recursion dep http://bugs.python.org/issue25274 15 msgs #25125: "Edit with IDLE" does not work for shortcuts http://bugs.python.org/issue25125 12 msgs #24820: IDLE themes for light on dark http://bugs.python.org/issue24820 11 msgs #25296: Simple End-of-life guide covering all unsupported versions http://bugs.python.org/issue25296 11 msgs #25256: Add sys.debug_build public variable to check if Python was com http://bugs.python.org/issue25256 9 msgs #18814: Add utilities to "clean" surrogate code points from strings http://bugs.python.org/issue18814 8 msgs #25001: Make --nowindows argument to regrtest propagate when running w http://bugs.python.org/issue25001 7 msgs #25275: Documentation v/s behaviour mismatch wrt integer literals cont http://bugs.python.org/issue25275 7 msgs #25276: Intermittent segfaults on PPC64 AIX 3.x http://bugs.python.org/issue25276 7 msgs Issues closed (56) ================== #10485: http.server fails when query string contains addition '?' char http://bugs.python.org/issue10485 closed by martin.panter #11215: test_fileio error on AIX http://bugs.python.org/issue11215 closed by haypo #12219: tkinter.filedialog.askopenfilename XT dialog on Windows 7 http://bugs.python.org/issue12219 closed by terry.reedy #14566: run_cgi reverts to using unnormalized path http://bugs.python.org/issue14566 closed by martin.panter #22413: Bizarre StringIO(newline="\r\n") translation http://bugs.python.org/issue22413 closed by pitrou #22609: Constructors of some mapping classes don't accept `self` keywo http://bugs.python.org/issue22609 closed by serhiy.storchaka #22958: Constructors of weakref mapping classes don't accept "self" an http://bugs.python.org/issue22958 closed by serhiy.storchaka #23546: Windows, 'Edit with IDLE', and multiple installed versions http://bugs.python.org/issue23546 closed by steve.dower #23600: tizinfo.fromutc changed for tzinfo wih StdOffset=0, DstOffset= http://bugs.python.org/issue23600 closed by belopolsky #24028: Idle: add doc subsection on calltips http://bugs.python.org/issue24028 closed by terry.reedy #24483: Avoid repeated hash calculation in C implementation of functoo http://bugs.python.org/issue24483 closed by serhiy.storchaka #24570: IDLE Autocomplete and Call Tips Do Not Pop Up on OS X with Act http://bugs.python.org/issue24570 closed by terry.reedy #24884: Add method reopenFile() in WatchedFileHandler class http://bugs.python.org/issue24884 closed by python-dev #24972: IDLE: revisit text highlighting for inactive windows on win32 http://bugs.python.org/issue24972 closed by terry.reedy #24988: IDLE: debugger context menus not working on Mac http://bugs.python.org/issue24988 closed by terry.reedy #25003: os.urandom() should call getrandom(2) not getentropy(2) on Sol http://bugs.python.org/issue25003 closed by haypo #25011: Smarter rl complete: hide private and special names http://bugs.python.org/issue25011 closed by serhiy.storchaka #25034: string.Formatter accepts empty fields but displays wrong when http://bugs.python.org/issue25034 closed by eric.smith #25091: Windows Installer uses small font http://bugs.python.org/issue25091 closed by steve.dower #25097: test_logging may fail with 'Access is denied' when pywin32 is http://bugs.python.org/issue25097 closed by vinay.sajip #25111: Broken compatibility in FrameSummary equality http://bugs.python.org/issue25111 closed by serhiy.storchaka #25123: Logging Documentation - dictConfig disable_existing_loggers http://bugs.python.org/issue25123 closed by vinay.sajip #25131: The AST for dict and set displays has the lineno of the first http://bugs.python.org/issue25131 closed by python-dev #25135: Deques to adopt the standard clearing procedure for mutable ob http://bugs.python.org/issue25135 closed by rhettinger #25165: Windows uninstallation should not remove launcher if other ver http://bugs.python.org/issue25165 closed by steve.dower #25171: does not build on OpenBSD with no value defined for PY_GETENTR http://bugs.python.org/issue25171 closed by haypo #25173: IDLE - several common dialogs don't have correct parent set http://bugs.python.org/issue25173 closed by terry.reedy #25182: python -v crashes in nonencodable directory http://bugs.python.org/issue25182 closed by serhiy.storchaka #25185: Inconsistency between venv and site http://bugs.python.org/issue25185 closed by python-dev #25186: Don't duplicate _verbose_message in importlib._bootstrap and _ http://bugs.python.org/issue25186 closed by brett.cannon #25203: Incorrect handling MemoryError in readline.set_completer_delim http://bugs.python.org/issue25203 closed by serhiy.storchaka #25209: Append space after completed keywords http://bugs.python.org/issue25209 closed by serhiy.storchaka #25211: Error message formatting errors in int object unit-test script http://bugs.python.org/issue25211 closed by martin.panter #25227: Optimize ASCII/latin1 encoder with surrogateescape error handl http://bugs.python.org/issue25227 closed by haypo #25233: AssertionError from asyncio Queue get http://bugs.python.org/issue25233 closed by gvanrossum #25234: test_eintr.test_os_open hangs under Xcode 7 http://bugs.python.org/issue25234 closed by brett.cannon #25236: str.maketrans wrong description for optional 3rd parameter http://bugs.python.org/issue25236 closed by BrianO #25241: ctypes: access violation reading http://bugs.python.org/issue25241 closed by eryksun #25245: Compile warnings in _pickle.c http://bugs.python.org/issue25245 closed by python-dev #25248: Discrepancy in unpickling integers with protocol 0 http://bugs.python.org/issue25248 closed by serhiy.storchaka #25249: Unneeded and unsafe mkstemp replacement in test_subprocess.py http://bugs.python.org/issue25249 closed by berker.peksag #25250: AttributeError: 'MSVCCompiler' object has no attribute '_MSVCC http://bugs.python.org/issue25250 closed by steve.dower #25253: AttributeError: 'Weather' object has no attribute 'dom' http://bugs.python.org/issue25253 closed by berker.peksag #25255: Security of CPython Builds http://bugs.python.org/issue25255 closed by r.david.murray #25260: python -m test --coverage doesn't work on Windows http://bugs.python.org/issue25260 closed by haypo #25261: Incorrect Return Values for any() and all() Built-in Functions http://bugs.python.org/issue25261 closed by zach.ware #25262: Issues with BINUNICODE8 and BINBYTES8 opcodes in pickle http://bugs.python.org/issue25262 closed by serhiy.storchaka #25265: Python install failed windows 8.1- Error 0x80240017: Failed to http://bugs.python.org/issue25265 closed by haypo #25267: Optimize UTF-8 encoder with error handlers http://bugs.python.org/issue25267 closed by haypo #25271: SystemError when doing codecs.escape_encode(b'') http://bugs.python.org/issue25271 closed by zach.ware #25273: Console interpreter holds a hard link on last displayed object http://bugs.python.org/issue25273 closed by eryksun #25279: Unexpected ftplib.error_xxx exception on SFTP 'STOR' command http://bugs.python.org/issue25279 closed by r.david.murray #25280: Message can be formatted twice in importlib http://bugs.python.org/issue25280 closed by serhiy.storchaka #25281: Incorrect enum behavior during json.dumps serialization http://bugs.python.org/issue25281 closed by r.david.murray #25284: Spec for BaseEventLoop.run_in_executor(executor, callback, *ar http://bugs.python.org/issue25284 closed by asvetlov #25288: readline.py file in current directory caused unexpected code e http://bugs.python.org/issue25288 closed by r.david.murray

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Issue #25256: Add sys.debug_build?
by Victor Stinner 02 Oct '15

02 Oct '15

Hi, I created the issue "Add sys.debug_build public variable to check if Python was compiled in debug mode": http://bugs.python.org/issue25256 I would like to add an obvious way to check if Python was compiled in debug mode, instead of having hacks/tips to check it. On the Internet, I found various recipes to check if Python is compiled is debug mode. Sadly, some of them are not portable. For example, 3 different checks are proposed on StackOverflow but 2 of them are specific to Windows: http://stackoverflow.com/questions/646518/python-how-to-detect-debug-interp… Even if the exact impact of a debug build depends on the Python implementation and the Python version, we can use it to have the same behaviour on all Python implementations. For example, the warnings module shows warnings by default if Python is compiled in debug mode: Extract of my patch: - if hasattr(sys, 'gettotalrefcount'): + if sys.debug_build: resource_action = "always" else: resource_action = "ignore" Alternative: Add a new sys.implementation.debug_build flag. Problem: extending sys.implementation requires a new PEP, and I don't think that debug_build fits into this object. Berker Peksag likes the idea. Serhiy Storchaka dislike the new flag: "I don't like this. The sys module is one of most used module, but it has too many members, and adding yet one makes the situation worse." (sys has 81 symbols) "Checking for debug mode is not often needed, and mainly in tests. Current way ``hasattr(sys, 'gettotalrefcount')`` works good. You also can check ``'d' in sys.abiflags`` if it looks cleaner to you. Or add a member to test.support." The name "debug_build" comes from the existing sysconfig.is_python_build() function. There is a sys.flags.debug flag, so "sys.debug" can be confusing. I prefer to attach the "build" suffix. First I proposed a function sys.is_debug_build(), but a flag is simpler than a function. There is not need to compute a version it's known at build time. What do you think? Should we add sys.debug_build? Victor

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PEP acceptance and SIGs
by Alexander Belopolsky 01 Oct '15

01 Oct '15

It has been my understanding that some PEPs may be discussed on specialized mailings lists, but a notice would be given on python-dev prior to any acceptance. I have recently received a notification that since PEP 470 has been accepted, I can no longer use external hosting for one of the packages that I published on PyPI. The PEP refers to a notice [1] posted on distutils-sig, but I cannot find any discussion of PEP 470 on either python-dev or python-ideas. [1]: https://mail.python.org/pipermail/distutils-sig/2015-September/026789.html

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