Nick Coghlan schrieb am So, 30. Okt 2011, um 09:32:18 +1000:

If people want to walk multiple directories, 3.3 will make that pretty easy:

def walk_dirs(dirs): for dir in dirs: yield from os.walk(dir)

In earlier versions you can use itertools.chain.from_iterable(map(os.walk, dirs)) to get an iterator that successively walks through the directory trees rooted at the directories in "dirs". -- Sven

On Sun, Oct 30, 2011 at 1:51 PM, John O'Connor <jxo6948@rit.edu> wrote:

...

No, because it means you end up having to special case strings so they're treated atomically. We already do that in a few string-specific APIs (e.g. startswith()/endswith()), but it's still not a particularly nice pattern.

It would be a special case, but I don't understand why that is a bad thing or why it is appropriate to do in some places but not others.

Maybe you forgot what the Zen of Python says about special cases. :-) "Special cases aren't special enough to break the rules."

Perhaps I am missing something. In this case, I think conceptually it makes sense to perform the "walk" on an iterable and also that one would expect strings to be treated atomically. I am well aware that not every 2-3 line recipe needs to be a new function but having more routines operate on iterables (where it makes sense) seems like a good idea.

It is often a good idea when the routine currently takes a specific iterable type (e.g. list). It is rarely a good idea to have a function that acts either on something of type X or a list of things of type X.

As an aside, I question the aesthetics of yet another for loop for the following. At least python has a nice for loop construct :)

for dir in dirs:    for root, dirs, files in os.walk(dir):        for name in files:            ....        for name in dirs:            ....

Whatever. :) -- --Guido van Rossum (python.org/~guido)

Nick Coghlan schrieb am So, 30. Okt 2011, um 09:32:18 +1000:

If people want to walk multiple directories, 3.3 will make that pretty easy:

def walk_dirs(dirs): for dir in dirs: yield from os.walk(dir)

In earlier versions you can use itertools.chain.from_iterable(map(os.walk, dirs)) to get an iterator that successively walks through the directory trees rooted at the directories in "dirs". -- Sven

On Sun, Oct 30, 2011 at 1:51 PM, John O'Connor <jxo6948@rit.edu> wrote:

...

No, because it means you end up having to special case strings so they're treated atomically. We already do that in a few string-specific APIs (e.g. startswith()/endswith()), but it's still not a particularly nice pattern.

It would be a special case, but I don't understand why that is a bad thing or why it is appropriate to do in some places but not others.

Maybe you forgot what the Zen of Python says about special cases. :-) "Special cases aren't special enough to break the rules."

Perhaps I am missing something. In this case, I think conceptually it makes sense to perform the "walk" on an iterable and also that one would expect strings to be treated atomically. I am well aware that not every 2-3 line recipe needs to be a new function but having more routines operate on iterables (where it makes sense) seems like a good idea.

It is often a good idea when the routine currently takes a specific iterable type (e.g. list). It is rarely a good idea to have a function that acts either on something of type X or a list of things of type X.

As an aside, I question the aesthetics of yet another for loop for the following. At least python has a nice for loop construct :)

for dir in dirs:    for root, dirs, files in os.walk(dir):        for name in files:            ....        for name in dirs:            ....

Whatever. :) -- --Guido van Rossum (python.org/~guido)