Re: PEP ? os.listdir enhancement
On Wed, 22 Jun 2005 11:27:06 -0500, Jeff Epler wrote: Why not just define the function yourself? Not every 3-line function needs to be built in. Of course I can code such a function, and I agree with the second sentence, but I think that obtaining absolutes path is a task so commonly needed that adding a keyword to an existing function would give a plus to the library without adding complexity (speaking of number of modules). Usually when you use os.listdir do you end using os.path.join to obtain absolutes path? I'm interested to know if the task is so common as I think, or if I'm wrong. Thank you, Riccardo -- Riccardo Galli Sideralis Programs http://www.sideralis.net -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
What's wrong with (os.path.join(d, x) for x in os.listdir(d)) It's short, and easier to understand then some obscure option ;) Andreas On Thu, Jun 23, 2005 at 11:05:57AM +0200, Riccardo Galli wrote: On Wed, 22 Jun 2005 11:27:06 -0500, Jeff Epler wrote: Why not just define the function yourself? Not every 3-line function needs to be built in. Of course I can code such a function, and I agree with the second sentence, but I think that obtaining absolutes path is a task so commonly needed that adding a keyword to an existing function would give a plus to the library without adding complexity (speaking of number of modules). Usually when you use os.listdir do you end using os.path.join to obtain absolutes path? I'm interested to know if the task is so common as I think, or if I'm wrong. Thank you, Riccardo -- Riccardo Galli Sideralis Programs http://www.sideralis.net -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
On 6/22/05, Riccardo Galli [EMAIL PROTECTED] wrote: I propose to add an 'abs' keyword which would make os.listdir return the absolute path of files instead of a relative path. What about os.listdir(dir='relative/path', abs=True)? Should listdir call abspath on results? Should we add another keyword rel? Would it complicate listdir unnecessarily? - kv -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
On Thu, 23 Jun 2005 11:34:02 +0200, Andreas Kostyrka wrote: What's wrong with (os.path.join(d, x) for x in os.listdir(d)) It's short, and easier to understand then some obscure option ;) Andreas how does it help in using list comprehension, as the ones in the first post? -- Riccardo Galli Sideralis Programs http://www.sideralis.net -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
On Thu, 23 Jun 2005 12:56:08 +0300, Konstantin Veretennicov wrote: On 6/22/05, Riccardo Galli [EMAIL PROTECTED] wrote: I propose to add an 'abs' keyword which would make os.listdir return the absolute path of files instead of a relative path. What about os.listdir(dir='relative/path', abs=True)? Should listdir call abspath on results? Should we add another keyword rel? Would it complicate listdir unnecessarily? - kv keyword dir not exists (don't know if you added as example or not) and abs set to true would return abspath on result. What else could it do ? -- Riccardo Galli Sideralis Programs http://www.sideralis.net -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
Riccardo Galli wrote: On Thu, 23 Jun 2005 12:56:08 +0300, Konstantin Veretennicov wrote: What about os.listdir(dir='relative/path', abs=True)? Should listdir call abspath on results? Should we add another keyword rel? Would it complicate listdir unnecessarily? keyword dir not exists (don't know if you added as example or not) and abs set to true would return abspath on result. What else could it do ? He probably meant that a 'join' option would be more natural than an 'abs' option. After all, your examples use os.path.join to create a valid path that can be used as the argument to other module os functions. Whether the results are absolute or relative should depend on the initial argument to os.listdir. Daniel -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
Konstantin Veretennicov wrote: On 6/22/05, Riccardo Galli [EMAIL PROTECTED] wrote: I propose to add an 'abs' keyword which would make os.listdir return the absolute path of files instead of a relative path. What about os.listdir(dir='relative/path', abs=True)? Should listdir call abspath on results? Should we add another keyword rel? Would it complicate listdir unnecessarily? - kv I'm in favour of Riccardo's suggestion, but I think he's got the name of the keyword wrong. The signature should be listdir(path, with_path=False) and cater absolute and relative paths alike. The need for such an enhancement is not particularly pressing, as workarounds abound. Here's another one: glob.glob(/usr/lib/games/../games/*) ['/usr/lib/games/../games/schwarzerpeter'] Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
Riccardo Galli wrote: On Thu, 23 Jun 2005 11:34:02 +0200, Andreas Kostyrka wrote: What's wrong with (os.path.join(d, x) for x in os.listdir(d)) It's short, and easier to understand then some obscure option ;) Andreas how does it help in using list comprehension, as the ones in the first post? You can nest list comprehension [ e for e in (os.path.join(d, x) for x in os.listdir(d)) if os.path.isdir (e)] You might also want to look at module itertools, which has better support for transforming and filtering in multiple steps. Daniel -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
On Thu, 23 Jun 2005 13:25:06 +0200, Daniel Dittmar wrote: He probably meant that a 'join' option would be more natural than an 'abs' option. After all, your examples use os.path.join to create a valid path that can be used as the argument to other module os functions. Whether the results are absolute or relative should depend on the initial argument to os.listdir. Daniel I got the point, and you're right. I didn't though about that and 'abs' as keyword becomes nonsense. Needing a more general kewyword, as pointed out by Peter Otten -- Riccardo Galli Sideralis Programs http://www.sideralis.net -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
Am Wed, 22 Jun 2005 17:57:14 +0200 schrieb Riccardo Galli: Hi, I noticed that when I use os.listdir I need to work with absolute paths 90% of times. While I can use a for cycle, I'd prefere to use a list comprehension, but it becomes too long. Hi, I like it. But as you noticed, too, join would be better than abs. Example: # mylistdir.py import os import sys def mylistdir(dir, join=False): for file in os.listdir(dir): yield os.path.join(dir, file) print list(mylistdir(sys.argv[1])) Thomas -- Thomas Güttler, http://www.thomas-guettler.de/ -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
Hi All-- Thomas Guettler wrote: I like it. But as you noticed, too, join would be better than abs. Example: # mylistdir.py import os import sys def mylistdir(dir, join=False): for file in os.listdir(dir): yield os.path.join(dir, file) print list(mylistdir(sys.argv[1])) Mmmm, how about: # mylistdir.py import os, os.path import sys def mylistdir(dir, join=False): for file in os.listdir(dir): if join: yield join(dir, file) else: yield file print list(mylistdir(sys.argv[1])) or print list(mylistdir(sys.argv[1],os.path.join)) That way I could def my own join and call it as print list(mylistdir(sys.argv[1],myjoin)) (Note that in your version the join argument isn't used at all.) Metta, Ivan -- Ivan Van Laningham God N Locomotive Works http://www.andi-holmes.com/ http://www.foretec.com/python/workshops/1998-11/proceedings.html Army Signal Corps: Cu Chi, Class of '70 Author: Teach Yourself Python in 24 Hours -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
On Thu, 23 Jun 2005 09:21:55 -0600, Ivan Van Laningham wrote: Mmmm, how about: # mylistdir.py import os, os.path import sys def mylistdir(dir, join=False): for file in os.listdir(dir): if join: yield join(dir, file) else: yield file print list(mylistdir(sys.argv[1])) or print list(mylistdir(sys.argv[1],os.path.join)) That way I could def my own join and call it as print list(mylistdir(sys.argv[1],myjoin)) I think that the implementation of listdir is done in C, so the functionality would be added in C too. by the way, I think 'join' (cute keyword) should be a boolean and not a callable: the obvious way is that we join path using os.path.join, and not some sophisticated function. With a boolean keyword code is smaller and if we want to use our special join function we can do it simply. e.g def func(dir,join=False): return (join and join(dir,x) or x for x in os.listdir(dir)) os.listdir is actually supposed not to be a generator, like you suggested. Are there known future changes ? Bye, Riccardo -- Riccardo Galli Sideralis Programs http://www.sideralis.net -- http://mail.python.org/mailman/listinfo/python-list
PEP ? os.listdir enhancement
Hi, I noticed that when I use os.listdir I need to work with absolute paths 90% of times. While I can use a for cycle, I'd prefere to use a list comprehension, but it becomes too long. I propose to add an 'abs' keyword which would make os.listdir return the absolute path of files instead of a relative path. This would bring only advantages, I think. I show two examples from os import listdir from os.path import isdir,join,getsize,isfile ### e.g. 1 part 1 - getting a list of directories ### dirs=[] for i in os.listdir(path): tmp_path=os.path.join(path,i) if os.path.isdir(tmp_path): dirs.append(tmp_path) ### e.g. 1 part 2 ### dirs=[join(path,x) for x in listdir(path) if isdir(join(path,x))] here the list comprehension is still clear, but only because we have direct references to join and friends. moreover whe need to use join twice for each directory. ### e.g. 2 part 1 - getting a list of (file,size) tuples ### path_size=[] for i in os.listdir(path): tmp_path=os.path.join(path,i) if os.path.isfile(tmp_path): path_size.append((tmp_path,getsize(tmp_path)) ### e.g. 2 part 2 ### dirs=[(join(path,x),getsize(join(path,x)) for x in listdir(path) if isfile(join(path,x))] now list comprehension is way too long, and in the worst case we must use join 3 times for each iteration. adding an 'abs' keyword to os.listdir would give benefits both to for cycle and list comprehensions. for cycle would lose the tmp_path assignment and list comprehensions ... ### e.g. 1 part 2 bis ### dirs=[x for x in listdir(path,abs=True) if isdir(x)] here we gain clearness and speed. ### e.g. 2 part 2 bis ### dirs=[(x,getsize(x)) for x in listdir(path,abs=True) if isfile(x)] and here we gain clearness, speed and a truely _usable_ list comprehension What do you think about this ? Thanks for reading, Riccardo -- Riccardo Galli Sideralis Programs http://www.sideralis.net -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
Why not just define the function yourself? Not every 3-line function needs to be built in. def listdir_joined(path): return [os.path.join(path, entry) for entry in os.listdir(path)] dirs = [x for x in listdir_joined(path) if os.path.isdir(x)] path_size = [(x, getsize(x)) for x in listdir_joined(path) if os.path.isfile(x)] Jeff pgpwXvnkgy6r4.pgp Description: PGP signature -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
Riccardo Galli wrote: I noticed that when I use os.listdir I need to work with absolute paths 90% of times. While I can use a for cycle, I'd prefere to use a list comprehension, but it becomes too long. ### e.g. 1 part 1 - getting a list of directories ### dirs=[] for i in os.listdir(path): tmp_path=os.path.join(path,i) if os.path.isdir(tmp_path): dirs.append(tmp_path) ### e.g. 1 part 2 ### dirs=[join(path,x) for x in listdir(path) if isdir(join(path,x))] Using Jason Orendorff's path module, all this code basically collapses down to this beauty (with your variable path renamed to myPath to avoid a name collision): from path import path dirs = path(myPath).abspath().dirs() -Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: PEP ? os.listdir enhancement
Peter Hansen wrote: Using Jason Orendorff's path module, all this code basically collapses down to this beauty (with your variable path renamed to myPath to avoid a name collision): This has to be the non-stdlib library I use the most. It's a great module. -- Michael Hoffman -- http://mail.python.org/mailman/listinfo/python-list
