[Python-Dev] A wart which should have been repaired in 3.0?

[rdmurray at bitdance.com]

On Tue, 30 Dec 2008 at 17:51, Phillip J. Eby wrote:
> At 02:32 PM 12/30/2008 -0800, Scott David Daniels wrote:
>> More trouble with the "just take the dirname":
>>
>>      paths = ['/a/b/c', '/a/b/d', '/a/b']
>>      os.path.dirname(os.path.commonprefix([
>>                          os.path.normpath(p) for p in paths]))
>> 
>> give '/a', not '/a/b'.
>
> ...because that's the correct answer.

But not the answer that is wanted.

So the challenge now is to write a single expression that will yield
'/a/b' when passed the above paths list, and also produce '/a/b' when
passed the following paths list:

     paths = ['/a/b/c', '/a/b/cd']

--RDM