Mailman 3 April 2009 - Python-Dev

Re: [Python-Dev] [Python-ideas] Proposed addtion to urllib.parse in 3.1 (and urlparse in 2.7)
by Mart Sõmermaa April 20, 2009

April 20, 2009

The general consensus in python-ideas is that the following is needed, so I bring it to python-dev to final discussions before I file a feature request in bugs.python.org. Proposal: add add_query_params() for appending query parameters to an URL to urllib.parse and urlparse. Implementation: http://github.com/mrts/qparams/blob/83d1ec287ec10934b5e637455819cf796b1b421… free to fork and comment). Behaviour (longish, guided by "simple things are simiple, complex things possible"): In the simplest form, parameters can be passed via keyword arguments: >>> add_query_params('foo', bar='baz') 'foo?bar=baz' >>> add_query_params('http://example.com/a/b/c?a=b', b='d') 'http://example.com/a/b/c?a=b&b=d' Note that '/', if given in arguments, is encoded: >>> add_query_params('http://example.com/a/b/c?a=b', b='d', foo='/bar') 'http://example.com/a/b/c?a=b&b=d&foo=%2Fbar' Duplicates are discarded: >>> add_query_params('http://example.com/a/b/c?a=b', a='b') 'http://example.com/a/b/c?a=b' >>> add_query_params('http://example.com/a/b/c?a=b&c=q', a='b', b='d', ... c='q') 'http://example.com/a/b/c?a=b&c=q&b=d' But different values for the same key are supported: >>> add_query_params('http://example.com/a/b/c?a=b', a='c', b='d') 'http://example.com/a/b/c?a=b&a=c&b=d' Pass different values for a single key in a list (again, duplicates are removed): >>> add_query_params('http://example.com/a/b/c?a=b', a=('q', 'b', 'c'), ... b='d') 'http://example.com/a/b/c?a=b&a=q&a=c&b=d' Keys with no value are respected, pass ``None`` to create one: >>> add_query_params('http://example.com/a/b/c?a', b=None) 'http://example.com/a/b/c?a&b' But if a value is given, the empty key is considered a duplicate (i.e. the case of a&a=b is considered nonsensical): >>> add_query_params('http://example.com/a/b/c?a', a='b', c=None) 'http://example.com/a/b/c?a=b&c' If you need to pass in key names that are not allowed in keyword arguments, pass them via a dictionary in second argument: >>> add_query_params('foo', {"+'|äüö": 'bar'}) 'foo?%2B%27%7C%C3%A4%C3%BC%C3%B6=bar' Order of original parameters is retained, although similar keys are grouped together. Order of keyword arguments is not (and can not be) retained: >>> add_query_params('foo?a=b&b=c&a=b&a=d', a='b') 'foo?a=b&a=d&b=c' >>> add_query_params('http://example.com/a/b/c?a=b&q=c&e=d', ... x='y', e=1, o=2) 'http://example.com/a/b/c?a=b&q=c&e=d&e=1&x=y&o=2' If you need to retain the order of the added parameters, use an :class:`OrderedDict` as the second argument (*params_dict*): >>> from collections import OrderedDict >>> od = OrderedDict() >>> od['xavier'] = 1 >>> od['abacus'] = 2 >>> od['janus'] = 3 >>> add_query_params('http://example.com/a/b/c?a=b', od) 'http://example.com/a/b/c?a=b&xavier=1&abacus=2&janus=3' If both *params_dict* and keyword arguments are provided, values from the former are used before the latter: >>> add_query_params('http://example.com/a/b/c?a=b', od, xavier=1.1, ... zorg='a', alpha='b', watt='c', borg='d') ' http://example.com/a/b/c?a=b&xavier=1&xavier=1.1&abacus=2&janus=3&zorg=a&bo… ' Do nothing with a single argument: >>> add_query_params('a') 'a' >>> add_query_params('arbitrary strange stuff?öäüõ*()+-=42') 'arbitrary strange stuff?\xc3\xb6\xc3\xa4\xc3\xbc\xc3\xb5*()+-=42'

10 29

Something like PEP-0304 - suppress *.pyc generation
by christian.doll＠basf.com April 20, 2009

April 20, 2009

Hello, im looking for something like PEP-0304 ( http://www.python.org/dev/peps/pep-0304/) I need something to suppress the generation of *.pyc files because i have very much different machines which call a python program at same time. the python program crashes at different places and on different machines - i think the problem are the *.pyc files of different machines which are generated at the same time. is pep-0304 implemented in a newer python version ( we use 2.4.4 ) or is there a work around or can someone implement pep-0304? thank you for your help! Viele Grüße Christian Doll

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#!/usr/bin/env python --> python3 where applicable
by Mitchell L Model April 18, 2009

April 18, 2009

Some library files, such as pdb.py, begin with #!/usr/bin/env python In various discussions regarding some issues I submitted I was told that the decision had been made to call Python 3.x release executables python3. (One of the conflicts I ran into when I made 'python' a link to python3.1 was that some tools used in making the HTML documentation haven't been upgraded to run with 3.) Shouldn't all library files that begin with the above line be changed so that they read 'python3' instead of python? Perhaps I should have just filed this as an issue, but I'm not confident of the state of the plan to move to python3 as the official executable name.

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RELEASED Python 2.6.2
by Barry Warsaw April 17, 2009

April 17, 2009

On behalf of the Python community, I'm happy to announce the availability of Python 2.6.2. This is the latest production-ready version in the Python 2.6 series. Dozens of issues have been fixed since Python 2.6.1 was released back in December. Please see the NEWS file for all the gory details. http://www.python.org/download/releases/2.6.2/NEWS.txt For more information on Python 2.6 in general, please see http://docs.python.org/dev/whatsnew/2.6.html Source tarballs, Windows installers, and (soon) Mac OS X disk images can be downloaded from the Python 2.6.2 page: http://www.python.org/download/releases/2.6.2/ Please report bugs for any Python version in the Python tracker: http://bugs.python.org Enjoy, -Barry Barry Warsaw barry(a)python.org Python 2.6/3.0 Release Manager (on behalf of the entire python-dev team)

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Re: [Python-Dev] Issue5434: datetime.monthdelta
by Jess Austin April 17, 2009

April 17, 2009

Jon Ribbens <jon+python-dev(a)unequivocal.co.uk> wrote: > On Thu, Apr 16, 2009 at 12:10:36PM +0400, Oleg Broytmann wrote: >> > This patch adds a "monthdelta" class and a "monthmod" function to the >> > datetime module. The monthdelta class is much like the existing >> > timedelta class, except that it represents months offset from a date, >> > rather than an exact period offset from a date. >> >> I'd rather see the code merged with timedelta: timedelta(months=n). > > Unfortunately, that's simply impossible. A timedelta is a fixed number > of seconds, and the time between one month and the next varies. I agree. > I am very much in favour of there being the ability to add months to > dates though. Obviously there is the question of what to do when you > move forward 1 month from the 31st January; in my opinion an optional > argument to specify different behaviours would be nice. Others have suggested raising an exception when a month calculation lands on an invalid date. Python already has that; it's spelled like this: >>> dt = date(2008, 1, 31) >>> dt.replace(month=dt.month + 1) Traceback (most recent call last): File "<stdin>", line 1, in <module> ValueError: day is out of range for month What other behavior options besides "last-valid-day-of-the-month" would you like to see? cheers, Jess

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Experimental and Test Tracker instances live
by Daniel (ajax) Diniz April 17, 2009

April 17, 2009

Hi, As discussed before, I have put two mock Python Tracker instances online. The Test[1] instance follows bugs.python.org code, so we can test bugfixes and procedures without breaking the real tracker. The Experimental[2] one, aka the cool instance, is where new features are showcased. Currently no emails are being sent and the dbs can be reset at any time. If you'd like to play as a registered user, please email me and I'll create a user (or activate the one you've started to register). So far, the new features[3] include: * Issue tags [4],[5] * Quiet properties [6] * Restore removed messages and files [7] * Claim ('assign to self') and add/remove self as nosy buttons [8] * Don't close issues with open dependencies [9] * Auto-add nosy users based on Components [10] * "Email me" buttons for messages and issues, "Reply by email" [11] * RSS feeds (per issue and global) [12] * Display selected issues in the index view [13] You can subscribe to a RSS feed[14] about the new features. Thanks to everyone who filled RFEs, there's still time to submit yours :) Regards, Daniel [1] http://bot.bio.br/python-dev/ [2] http://bot.bio.br/python-dev-exp/ [3] http://bot.bio.br/python-dev-exp/issue5 [4] http://mail.python.org/pipermail/tracker-discuss/2009-April/002099.html [5] http://codereview.appspot.com/40100/show [6] http://psf.upfronthosting.co.za/roundup/meta/issue249 [7] http://psf.upfronthosting.co.za/roundup/meta/issue267 [8] http://psf.upfronthosting.co.za/roundup/meta/issue258 [9] http://psf.upfronthosting.co.za/roundup/meta/issue266 [10] http://psf.upfronthosting.co.za/roundup/meta/issue258 [11] http://psf.upfronthosting.co.za/roundup/meta/issue245 [12] http://psf.upfronthosting.co.za/roundup/meta/issue155 [13] http://psf.upfronthosting.co.za/roundup/meta/issue246 [14] http://bot.bio.br/python-dev-exp/issue5?@template=feed

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Summary of Python tracker Issues
by Python tracker April 17, 2009

April 17, 2009

ACTIVITY SUMMARY (04/10/09 - 04/17/09) Python tracker at http://bugs.python.org/ To view or respond to any of the issues listed below, click on the issue number. Do NOT respond to this message. 2222 open (+37) / 15383 closed (+12) / 17605 total (+49) Open issues with patches: 852 Average duration of open issues: 642 days. Median duration of open issues: 393 days. Open Issues Breakdown open 2168 (+37) pending 54 ( +0) Issues Created Or Reopened (50) _______________________________ ignore py3_test_grammar.py syntax error 04/11/09 CLOSED http://bugs.python.org/issue5733 reopened benjamin.peterson BufferedRWPair broken 04/11/09 http://bugs.python.org/issue5734 created bquinlan patch Segfault when loading not recompiled module 04/11/09 http://bugs.python.org/issue5735 created chin patch, needs review Add the iterator protocol to dbm modules 04/11/09 http://bugs.python.org/issue5736 created akitada patch add Solaris errnos 04/11/09 http://bugs.python.org/issue5737 created mahrens easy multiprocessing example wrong 04/11/09 http://bugs.python.org/issue5738 created yaneurabeya Language reference is ambiguous regarding next() method lookup 04/12/09 http://bugs.python.org/issue5739 created ncoghlan multiprocessing.connection.Client API documentation incorrect 04/12/09 http://bugs.python.org/issue5740 created yaneurabeya SafeConfigParser incorrectly detects lone percent signs 04/12/09 CLOSED http://bugs.python.org/issue5741 created marcio inspect.findsource() should look only for sources 04/12/09 http://bugs.python.org/issue5742 created hdima patch multiprocessing.managers not accessible even though docs say so 04/12/09 CLOSED http://bugs.python.org/issue5743 created yaneurabeya multiprocessing.managers.BaseManager.connect example typos 04/12/09 CLOSED http://bugs.python.org/issue5744 reopened quiver email document update (more links) 04/13/09 CLOSED http://bugs.python.org/issue5745 created ocean-city patch socketserver problem upon disconnection (undefined member) 04/13/09 CLOSED http://bugs.python.org/issue5746 created eblond knowing the parent command 04/13/09 http://bugs.python.org/issue5747 created tarek Objects/bytesobject.c should include stringdefs.h, instead of de 04/13/09 http://bugs.python.org/issue5748 created eric.smith easy Allow bin() to have an optional "Total Bits" argument. 04/14/09 CLOSED http://bugs.python.org/issue5749 created MechPaul weird seg fault 04/14/09 CLOSED http://bugs.python.org/issue5750 created utilitarian Typo in documentation of print function parameters 04/14/09 http://bugs.python.org/issue5751 created nicolasg xml.dom.minidom does not handle newline characters in attribute 04/14/09 http://bugs.python.org/issue5752 created Tomalak CVE-2008-5983 python: untrusted python modules search path 04/14/09 http://bugs.python.org/issue5753 created iankko patch Shelve module writeback parameter does not act as advertised 04/14/09 http://bugs.python.org/issue5754 created jherskovic "-Wstrict-prototypes" is valid for Ada/C/ObjC but not for C++" 04/14/09 http://bugs.python.org/issue5755 created zooko idle pydoc et al removed from 3.1 without versioned replacements 04/14/09 http://bugs.python.org/issue5756 created nad Documentation error for Condition.notify() 04/14/09 http://bugs.python.org/issue5757 created pietvo fileinput.hook_compressed returning bytes from gz file 04/14/09 http://bugs.python.org/issue5758 created mnewman __float__ not called by 'float' on classes derived from str 04/15/09 CLOSED http://bugs.python.org/issue5759 created shura_zam patch __getitem__ error message hard to understand 04/15/09 http://bugs.python.org/issue5760 created cvrebert add file name to py3k IO objects repr() 04/15/09 http://bugs.python.org/issue5761 created pitrou AttributeError: 'NoneType' object has no attribute 'replace' 04/15/09 http://bugs.python.org/issue5762 created hda scope resolving error 04/15/09 CLOSED http://bugs.python.org/issue5763 created vpodpecan 2.6.2 Python Manuals CHM file seems broken 04/15/09 http://bugs.python.org/issue5764 created dx617 stack overflow evaluating eval("()" * 30000) 04/15/09 http://bugs.python.org/issue5765 created gagenellina Mac/scripts/BuildApplet.py reset of sys.executable during instal 04/16/09 http://bugs.python.org/issue5766 created blb xmlrpclib loads invalid documents 04/16/09 http://bugs.python.org/issue5767 created exarkun logging don't encode Unicode message correctly. 04/16/09 CLOSED http://bugs.python.org/issue5768 created naoki patch OS X Installer: new make of documentation installs at wrong loca 04/16/09 http://bugs.python.org/issue5769 created nad SA bugs with unittest.py 04/16/09 CLOSED http://bugs.python.org/issue5770 created yaneurabeya patch SA bugs with unittest.py@r71263 04/16/09 http://bugs.python.org/issue5771 created yaneurabeya patch For float.__format__, don't add a trailing ".0" if we're using n 04/16/09 http://bugs.python.org/issue5772 created eric.smith easy Crash on shutdown after os.fdopen(2) in debug builds 04/16/09 http://bugs.python.org/issue5773 created amaury.forgeotdarc _winreg.OpenKey() is documented with keyword arguments, but does 04/16/09 http://bugs.python.org/issue5774 created stutzbach marshal.c needs to be checked for out of memory errors 04/16/09 http://bugs.python.org/issue5775 created eric.smith RPM build error with python-2.6.spec 04/17/09 http://bugs.python.org/issue5776 created yasusii patch unable to search in python V3 documentation 04/17/09 http://bugs.python.org/issue5777 created aotto1968 sys.version format differs between MSC and GCC 04/17/09 http://bugs.python.org/issue5778 created t-kamiya _elementtree import can fail silently 04/17/09 CLOSED http://bugs.python.org/issue5779 created naufraghi test_float fails for 'legacy' float repr style 04/17/09 http://bugs.python.org/issue5780 created marketdickinson patch Legacy float repr is used unnecessarily on some platforms 04/17/09 http://bugs.python.org/issue5781 created marketdickinson easy ',' formatting with empty format type '' (PEP 378) 04/17/09 http://bugs.python.org/issue5782 created eric.smith easy Issues Now Closed (37) ______________________ Use shorter float repr when possible 493 days http://bugs.python.org/issue1580 marketdickinson patch "make altinstall" installs pydoc, idle, smtpd.py 490 days http://bugs.python.org/issue1590 nad patch PyString_FromStringAndSize() to be considered unsafe 369 days http://bugs.python.org/issue2587 psss PyOS_vsnprintf() underflow leads to memory corruption 371 days http://bugs.python.org/issue2588 psss patch Handle ASDLSyntaxErrors gracefully 347 days http://bugs.python.org/issue2725 georg.brandl patch Starting any program as a subprocess fails when subprocess.Popen 265 days http://bugs.python.org/issue3440 r.david.murray patch Allow Division of datetime.timedelta Objects 156 days http://bugs.python.org/issue4291 Jeremy Banks asyncore's urgent data management and connection closed events 131 days http://bugs.python.org/issue4501 r.david.murray patch handling inf/nan in '%f' 101 days http://bugs.python.org/issue4799 eric.smith patch native build of python win32 using msys under wine. 90 days http://bugs.python.org/issue4954 lritter test_maxint64 fails on 32-bit systems due to assumption that 64- 81 days http://bugs.python.org/issue4977 pitrou io-c: TextIOWrapper is faster than BufferedReader but not protec 25 days http://bugs.python.org/issue5502 pitrou patch Lib/distutils/test/test_util: test_get_platform bogus for OSX 14 days http://bugs.python.org/issue5607 tarek Add more pickling tests 14 days http://bugs.python.org/issue5665 collinwinter patch, needs review string module requires bytes type for maketrans, but calling met 10 days http://bugs.python.org/issue5675 georg.brandl pydoc -w doesn't produce proper HTML 6 days http://bugs.python.org/issue5698 georg.brandl patch, patch, needs review inside *currentmodule* some links is disabled 7 days http://bugs.python.org/issue5703 georg.brandl Command line option '-3' should imply '-t' 7 days http://bugs.python.org/issue5704 georg.brandl setuptools doesn't honor standard compiler variables 7 days http://bugs.python.org/issue5706 tarek Tiny code polishing to unicode_repeat 6 days http://bugs.python.org/issue5708 georg.brandl patch optparse: please provide a usage example in the module docstring 5 days http://bugs.python.org/issue5719 georg.brandl ignore py3_test_grammar.py syntax error 0 days http://bugs.python.org/issue5733 benjamin.peterson SafeConfigParser incorrectly detects lone percent signs 1 days http://bugs.python.org/issue5741 georg.brandl multiprocessing.managers not accessible even though docs say so 0 days http://bugs.python.org/issue5743 yaneurabeya multiprocessing.managers.BaseManager.connect example typos 0 days http://bugs.python.org/issue5744 yaneurabeya email document update (more links) 0 days http://bugs.python.org/issue5745 georg.brandl patch socketserver problem upon disconnection (undefined member) 1 days http://bugs.python.org/issue5746 benjamin.peterson Allow bin() to have an optional "Total Bits" argument. 0 days http://bugs.python.org/issue5749 rhettinger weird seg fault 0 days http://bugs.python.org/issue5750 amaury.forgeotdarc __float__ not called by 'float' on classes derived from str 1 days http://bugs.python.org/issue5759 benjamin.peterson patch scope resolving error 0 days http://bugs.python.org/issue5763 marketdickinson logging don't encode Unicode message correctly. 1 days http://bugs.python.org/issue5768 vsajip patch SA bugs with unittest.py 0 days http://bugs.python.org/issue5770 benjamin.peterson patch _elementtree import can fail silently 0 days http://bugs.python.org/issue5779 naufraghi DistributionMetaData error ? 2217 days http://bugs.python.org/issue708320 varash file.seek() influences write() when opened with a+ mode 1008 days http://bugs.python.org/issue1521491 amaury.forgeotdarc Popen pipe file descriptor leak on OSError in init 641 days http://bugs.python.org/issue1751245 benjamin.peterson Top Issues Most Discussed (10) ______________________________ 10 io.FileIO calls flush() after file closed 12 days open http://bugs.python.org/issue5700 9 Add the iterator protocol to dbm modules 6 days open http://bugs.python.org/issue5736 7 2.6.2c1 fails to pass test_cmath on Solaris10 9 days open http://bugs.python.org/issue5724 6 test_float fails for 'legacy' float repr style 0 days open http://bugs.python.org/issue5780 6 Add test.support.import_python_only 53 days open http://bugs.python.org/issue5354 6 10e667.__format__('+') should return 'inf' 137 days open http://bugs.python.org/issue4482 5 ignore py3_test_grammar.py syntax error 0 days closed http://bugs.python.org/issue5733 5 setdefault speedup 8 days open http://bugs.python.org/issue5730 5 Support telling TestResult objects a test run has finished 8 days open http://bugs.python.org/issue5728 5 IDLE shell gives different len() of unicode strings compared to 973 days open http://bugs.python.org/issue1542677

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Re: [Python-Dev] Python-Dev Digest, Vol 69, Issue 143
by Jess Austin April 17, 2009

April 17, 2009

Jared Grubb <jared.grubb(a)gmail.com> wrote: > On 16 Apr 2009, at 11:42, Paul Moore wrote: >> The key thing missing (I believe) from dateutil is any equivalent of >> monthmod. > > > I agree with that. It's well-defined and it makes a lot of sense. +1 > > But, I dont think monthdelta can be made to work... what should the > following be? >>> print(date(2008,1,30) + monthdelta(1)) 2008-02-29 >>> print(date(2008,1,30) + monthdelta(2)) 2008-03-30 >>> print(date(2008,1,30) + monthdelta(1) + monthdelta(1)) 2008-03-29 This is a perceptive observation: in the absence of parentheses to dictate a different order of operations, the third quantity will differ from the second. Furthermore, this won't _always_ be true, just for dates near the end of the month, which is nonintuitive. (Incidentally, this is another reason why this functionality should not just be lumped into timedelta; guarantees that have long existed for operations with timedelta would no longer hold if it tried to deal with months.) I find that date calculations involving months involve a certain amount of inherent confusion. I've tried to reduce this by introducing well-specified functionality that will allow accurate reasoning, as part of the core's included batteries. I think that one who uses these objects will develop an intuition and write accurate code quickly. It is nonintuitive that order of operation matters for addition of months, just as it matters for subtraction and division of all objects, but with the right tools we can deal with this. An interesting consequence is that if I want to determine if date b is more than a month after date a, sometimes I should use: b - monthdelta(1) > a rather than a + monthdelta(1) < b [Consider a list of run dates for a process that should run the last day of every month: "a" might be date(2008, 2, 29) while "b" is date(2008, 3, 31). In this case the two expressions would have different values.] cheers, Jess

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Re: [Python-Dev] Issue5434: datetime.monthdelta
by Jess Austin April 17, 2009

April 17, 2009

Antoine Pitrou <solipsis(a)pitrou.net> wrote: > Jess Austin <jess.austin <at> gmail.com> writes: >> >> What other behavior options besides "last-valid-day-of-the-month" >> would you like to see? > > IMHO, the question is rather what the use case is for the behaviour you are > proposing. In which kind of situation is it acceptable to turn 31/2 silently > into 29/2? I have worked in utility/telecom billing, and needed to examine large numbers of invoice dates, fulfillment dates, disconnection dates, payment dates, collection event dates, etc. There would often be particular rules for the relationships among these dates, and since many companies generate invoices every day of the month, you couldn't rely on rules like "this always happens on the 5th". Here is an example (modified) from the doc page. We want to find missing invoices: >>> invoices = {123: [date(2008, 1, 31), ... date(2008, 2, 29), ... date(2008, 3, 31), ... date(2008, 4, 30), ... date(2008, 5, 31), ... date(2008, 6, 30), ... date(2008, 7, 31), ... date(2008, 12, 31)], ... 456: [date(2008, 1, 1), ... date(2008, 5, 1), ... date(2008, 6, 1), ... date(2008, 7, 1), ... date(2008, 8, 1), ... date(2008, 11, 1), ... date(2008, 12, 1)]} >>> for account, dates in invoices.items(): ... a = dates[0] ... for b in dates[1:]: ... if b - monthdelta(1) > a: ... print('account', account, 'missing between', a, 'and', b) ... a = b ... account 456 missing between 2008-01-01 and 2008-05-01 account 456 missing between 2008-08-01 and 2008-11-01 account 123 missing between 2008-07-31 and 2008-12-31 In general, sometimes we care more about the number of months that separate dates than we do about the exact dates themselves. This is perhaps not the most common situation for date calculations, but it does come up for some of us. I tired of writing one-off solutions that would fail in unexpected corner cases, so I created this patch. Paul Moore has also described his favorite use-case for this functionality. cheers, Jess

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Re: [Python-Dev] PEP 382: Namespace Packages
by P.J. Eby April 17, 2009

April 17, 2009

At 03:58 AM 4/17/2009 +0000, glyph(a)divmod.com wrote: >Just as a use-case: would the Java "com.*" namespace be an example >of a "pure package with no base"? i.e. lots of projects are in it, >but no project owns it? Er, I suppose. I was thinking more of the various 'com.foo' and 'org.bar' packages as being the pure namespaces in question. For Python, a "flat is better than nested" approach seems fine at the moment. >Just to clarify things on my end: "namespace package" to *me* means >"package with modules provided from multiple distributions (the >distutils term)". The definition provided by the PEP, that a >package is spread over multiple directories on disk, seems like an >implementation detail. Agreed. >Entries on __path__ slow down import, so my understanding of the >platonic ideal of a system python installation is one which has a >single directory where all packages reside, and a set of metadata >off to the side explaining which files belong to which distributions >so they can be uninstalled by a package manager. True... except that part of the function of the PEP is to ensure that if you install those separately-distributed modules to the same directory, it still needs to work as a package and not have any inter-package file conflicts. >Of course, for a development installation, easy uninstallation and >quick swapping between different versions of relevant dependencies >is more important than good import performance. So in that case, >you would want to optimize differently by having all of your >distributions installed into separate directories, with a long >PYTHONPATH or lots of .pth files to point at them. > >And of course you may want a hybrid of the two. Yep. >So another clarification I'd like in the PEP is an explanation of >motivation. For example, it comes as a complete surprise to me that >the expectation of namespace packages was to provide only >single-source namespaces like zope.*, peak.*, twisted.*. As I >mentioned above, I implicitly thought this was more for com.*, >twisted.plugins.*. Well, aside from twisted.plugins, I wasn't aware of anybody in Python doing that... and as I described, I never really interpreted that through the lens of "namespace package" vs. "plugin finding". >Right now it just says that it's a package which resides in multiple >directories, and it's not made clear why that's a desirable feature. Good point; perhaps you can suggest some wording on these matters to Martin? >Okay. So what I'm hearing is that Twisted should happily continue >using our own wacky __path__-calculation logic for twisted.plugins, >but that *twisted* should be a namespace package so that our >separate distributions (TwistedCore, TwistedWeb, TwistedConch, et. >al.) can be installed into separate directories. Yes. Thanks for taking the time to participate in this and add another viewpoint to the mix, not to mention clarifying some areas where the PEP could be clearer.

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