Mailman 3 January 2002 - Python-Dev

RE: [Python-Dev] Those import related syntax errors again...
by Samuele Pedroni 23 Feb '05

23 Feb '05

Hi. [Mark Hammond] > The point isn't about my suffering as such. The point is more that > python-dev owns a tiny amount of the code out there, and I don't believe we > should put Python's users through this. > > Sure - I would be happy to "upgrade" all the win32all code, no problem. I > am also happy to live in the bleeding edge and take some pain that will > cause. > > The issue is simply the user base, and giving Python a reputation of not > being able to painlessly upgrade even dot revisions. I agree with all this. [As I imagined explicit syntax did not catch up and would require lot of discussions.] [GvR] > > Another way is to use special rules > > (similar to those for class defs), e.g. having > > > > <frag> > > y=3 > > def f(): > > exec "y=2" > > def g(): > > return y > > return g() > > > > print f() > > </frag> > > > > # print 3. > > > > Is that confusing for users? maybe they will more naturally expect 2 > > as outcome (given nested scopes). > > This seems the best compromise to me. It will lead to the least > broken code, because this is the behavior that we had before nested > scopes! It is also quite easy to implement given the current > implementation, I believe. > > Maybe we could introduce a warning rather than an error for this > situation though, because even if this behavior is clearly documented, > it will still be confusing to some, so it is better if we outlaw it in > some future version. > Yes this can be easy to implement but more confusing situations can arise: <frag> y=3 def f(): y=9 exec "y=2" def g(): return y return y,g() print f() </frag> What should this print? the situation leads not to a canonical solution as class def scopes. or <frag> def f(): from foo import * def g(): return y return g() print f() </frag> [Mark Hammond] > > This probably won't be a very popular suggestion, but how about pulling > > nested scopes (I assume they are at the root of the problem) > > until this can be solved cleanly? > > Agreed. While I think nested scopes are kinda cool, I have lived without > them, and really without missing them, for years. At the moment the cure > appears worse then the symptoms in at least a few cases. If nothing else, > it compromises the elegant simplicity of Python that drew me here in the > first place! > > Assuming that people really _do_ want this feature, IMO the bar should be > raised so there are _zero_ backward compatibility issues. I don't say anything about pulling nested scopes (I don't think my opinion can change things in this respect) but I should insist that without explicit syntax IMO raising the bar has a too high impl cost (both performance and complexity) or creates confusion. [Andrew Kuchling] > >Assuming that people really _do_ want this feature, IMO the bar should be > >raised so there are _zero_ backward compatibility issues. > > Even at the cost of additional implementation complexity? At the cost > of having to learn "scopes are nested, unless you do these two things > in which case they're not"? > > Let's not waffle. If nested scopes are worth doing, they're worth > breaking code. Either leave exec and from..import illegal, or back > out nested scopes, or think of some better solution, but let's not > introduce complicated backward compatibility hacks. IMO breaking code would be ok if we issue warnings today and implement nested scopes issuing errors tomorrow. But this is simply a statement about principles and raised impression. IMO import * in an inner scope should end up being an error, not sure about 'exec's. We will need a final BDFL statement. regards, Samuele Pedroni.

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Extending types in C - help needed
by Jack Jansen 08 Feb '02

08 Feb '02

In the discussion on my request for an ("O@", typeobject, void **) format for PyArg_Parse and Py_BuildValue MAL suggested that I could get the same functionality by creating a type WrapperTypeObject, which would be a subtype of TypeObject with extra fields pointing to the _New() and _Convert() routines to convert Python objects from/to C pointers. This would be good enough for me, because then types wanting to participate in the wrapper protocol would subtype WrapperTypeObject in stead of TypeObject, and two global routines could return the _New and _Convert routines given the type object, and we wouldn't need yet another PyArg_Parse format specifier. However, after digging high and low I haven't been able to deduce how I would then use this WrapperType in C as the type for my extension module objects. Are there any examples? If not, could someone who understands the new inheritance scheme give me some clues as to how to do this? -- - Jack Jansen <Jack.Jansen(a)oratrix.com> http://www.cwi.nl/~jack - - If I can't dance I don't want to be part of your revolution -- Emma Goldman -

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Re: [Python-checkins] CVS: python/dist/src/Mac/scripts gensuitemodule.py,1.18,1.19
by Guido van Rossum 06 Feb '02

06 Feb '02

> The keyword module has an undocumented data object kwlist which is a > list of keywords. Perhaps this should be documented and made part of > the public API? I'd want to change the list to a tuple, but that > seems harmless since it isn't already part of the API. Why make it a tuple? Out of fear someone changes it? Let them change it, and learn about sharing of object references! Agree it should be documented of course. --Guido van Rossum (home page: http://www.python.org/~guido/)

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distutils & stderr
by Skip Montanaro 03 Feb '02

03 Feb '02

If I could "cvs up" I would submit a patch, but in the meantime, is there any good reason that distutils shouldn't write its output to stderr? I'm using PyInline to execute a little bit of C code that returns some information about the system to the calling Python code. This code then sends some output to stdout. I've patched my local directory tree so that distutils sends its output to sys.stderr. Is there some overriding reason distutils messages should go to sys.stdout? BTW, Python + PyInline makes a hell of a lot easier to understand configure script... ;-) Skip

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opcode performance measurements
by Jeremy Hylton 02 Feb '02

02 Feb '02

I've made some simple measurements of how long opcodes take to execute and how long it takes to go around the mainloop, using the Pentim timestamp counter, which measures processor cycles. The results aren't particularly surprising, but they provide some empirical validation of what we've believed all along. I don't have time to go into all the gory details here, though I plan to at Spam 10 developers day next week. I put together a few Web pages that summarize the data I've collected on some simple benchmarks: http://www.zope.org/Members/jeremy/CurrentAndFutureProjects/PerformanceMeas… Comments and questions are welcome. I've got a little time to do more measurement and analysis before devday. Jeremy

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next vs darwin
by Steven Majewski 01 Feb '02

01 Feb '02

I recall having the discussion but I don't quite recall the resolution: Is Next support now officially dropped from the distribution ? I have a revised dynamic loading module that strips out all of the dead branches ( as well as better error reporting ): I was going to call it dynload_darwin.c and add support to configure, but grepping thru configure I only saw darwin as triggering dynload_next.c -- it *looks* like the Next has bee dropped. Should we rename the file anyway ? ( to make it easier for folks to know where to look. ) There has also been some discussion on the pythonmac-sig list about dynamic loading. There are some other problems that this module doesn't fix yet. If someone wants to subit a better one, that's fine by me, but we REALLY need to get the better error reporting in there so we can at least find the problem. The other thing that's been discussed is adding configure support to build with the dlopen compatability libs if that is available. ( doing config with --without-dyld doesn't seem to change anything. ) -- Steve

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Fwd: [Pythonmac-SIG] sys.exit() functionality
by Jack Jansen 31 Jan '02

31 Jan '02

This discussion started on pythonmac-SIG, but someone suggested that it isn't really a MacPython-specific issue (even though the implementation will be different for MacPython from unix-Python). Any opinions? Begin forwarded message: > From: Martin Miller <mmiller(a)adobe.com> > Date: Wed Jan 30, 2002 08:14:13 PM Europe/Amsterdam > To: pythonmac-sig(a)python.org > Subject: Re: [Pythonmac-SIG] sys.exit() functionality > > On Wed, 30 Jan 2002 15:29:21 +0100, Jack Jansen wrote: >> >> On Tuesday, January 29, 2002, at 08:54 , Jon Bradley wrote: >> >>> hey all, >>> >>> In embedded Python - why does sys.exit() quit out of the application >>> that's >>> embedding the interpreter? Is there any way to trap or >>> disregard this? >>> >>> If a user creates an application with Python and runs it through the >>> embedded interpreter, calling quit or exit on the Python application >>> itself >>> is more than ok, but allowing it to force out of the parent >>> application >>> isn't. >> >> Sounds reasonable. How about a routine PyMac_SetExitFunc() that you >> could call to set your own exit function, (similar to >> PyMac_SetConsoleHandler())? MacPython would then do all it's normal >> cleanup, but at the very end call your routine in stead of exit(). > > With an approach like the above, wouldn't it be better to have a > platform-independent way of defining a custom exit function, > rather than > calling a Mac-only system function -- or is this whole thing only an > issue with MacPython embedding? > > Martin > > _______________________________________________ > Pythonmac-SIG maillist - Pythonmac-SIG(a)python.org > http://mail.python.org/mailman/listinfo/pythonmac-sig > -- - Jack Jansen <Jack.Jansen(a)oratrix.com> http://www.cwi.nl/~jack - - If I can't dance I don't want to be part of your revolution -- Emma Goldman -

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Attention Mailman list administrators
by barry＠zope.com 31 Jan '02

31 Jan '02

You will soon notice (if you haven't already) that your list admin passwords on mail.python.org are broken. This happened due to an upgrade of the version of Python running on that system. The old list passwords can't be recovered, so they have to be reset. List administrators can contact me to get this done. If you know the old password, send it to me and I'll reset the list to it. Otherwise, let me know and I'll generate a new password for you. Sorry for the inconvenience, -Barry

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Thread questionlet
by Christian Tismer 31 Jan '02

31 Jan '02

Dear developers, I'm still a little ignorant to real threads. In order to do the implementation of hard-wired microthreads right, I tried to understand how real threads work. My question, which I could not easily answer by reading the source is: What happens when the main thread ends? Do all threads run until they are eady too, or are they just killed away? And if they are killed, are they just removed, or do they all get an exception for cleanup? I would guess the latter, but I'm not sure. When a thread ends, it may contain several levels of other C calls which might need to finalize, so I thought of a special exception for this, but didn't find such. Many thanks and sorry about my ignorance - chris -- Christian Tismer :^) <mailto:tismer@tismer.com> Mission Impossible 5oftware : Have a break! Take a ride on Python's Kaunstr. 26 : *Starship* http://starship.python.net/ 14163 Berlin : PGP key -> http://wwwkeys.pgp.net/ PGP Fingerprint E182 71C7 1A9D 66E9 9D15 D3CC D4D7 93E2 1FAE F6DF where do you want to jump today? http://www.stackless.com/

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updated patches for OS/2 EMX port
by Andrew MacIntyre 31 Jan '02

31 Jan '02

Its taken longer than I'd hoped, however they're finally up for review. The updated bits have been attached to the previous patch entries in the patch manager: 435381: distutils changes http://sf.net/tracker/?func=detail&atid=305470&aid=435381&group_id=5470 450265: build files - self contained subdirectory in PC/ http://sf.net/tracker/?func=detail&atid=305470&aid=450265&group_id=5470 450266: library changes - 3 patch files covering:- - Lib/ (included os2emxpath.py as previously discussed here) - Lib/plat-os2emx/ (new subdirectory) - Lib/test/ (cope with 2 EMX limitations) http://sf.net/tracker/?func=detail&atid=305470&aid=450266&group_id=5470 450267: core changes - 4 patch files covering:- - Include/ - Modules/ (lots of changes; see below for more info) - Objects/ (see below for more info) - Python/ http://sf.net/tracker/?func=detail&atid=305470&aid=450267&group_id=5470 I hope that I got the patch links right... Particular notes wrt #450267: - the patch to Modules/import.c supports VACPP in addition to EMX. Michael Muller has trialled this patch with a VACPP build successfully. It is messy, but OS/2 isn't going to lose the 8.3 naming limit on DLLs anytime soon :-( Although truncating the DLL (PYD) name to 8 characters increases the chances of a name clash, the case-sensitive import support in the same patch alleviates it somewhat, and the fact that the "init<module>" entrypoint is maintained will result in an import failure when there is an actual name clash. - Modules/unicodedata.c is affected by a name clash between the internally defined _getname() and an EMX routine of the same name defined in <stdlib.h>. The patch renames the internal routine to _getucname() to avoid this, but this change may not be acceptable - advice please. - Objects/stringobject.c and Objects/unicodeobject.c contain changes to handle the EMX runtime library returning "0x" as the prefix for output formatted with a "%X" format. I have tried to minimise the changes in these patches to the minimum needed for the port to function, ie I've tried to eradicate the cosmetic changes in the earlier patches, and avoid picking up unwanted files (such as Modules/Setup). Please let me know if you find any such changes I missed. The patches uploaded apply cleanly to a copy of an anonoymously checked out CVS tree as of 0527 AEST this morning (Jan 27), and have been built and regression tested on both OS/2 EMX and FreeBSD 4.4R with no unexpected test failures. If there are no unresolvable objections, and approval to apply these patches is granted, I propose that the patches be applied as follows:- Stage 1: the build patch (creates+populates PC/os2emx/) Stage 2: the Lib/plat-os2emx/ patch Stage 3: the Lib/ and Lib/test/ patches Stage 4: the distutils patch Stage 5: the Include/, Objects/ and Python/ patches Stage 6: the Modules/ patch I would expect to allow at least 48 hours between stages. Comments/advice on this proposal also appreciated. -- Andrew I MacIntyre "These thoughts are mine alone..." E-mail: andymac(a)bullseye.apana.org.au | Snail: PO Box 370 andymac(a)pcug.org.au | Belconnen ACT 2616 Web: http://www.andymac.org/ | Australia

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