std.path review: update

[Steven Schveighoffer]

On Mon, 18 Jul 2011 14:30:51 -0400, Lars T. Kyllingstad  
<public at kyllingen.nospamnet> wrote:

> On Mon, 18 Jul 2011 13:26:08 -0400, Steven Schveighoffer wrote:
>
>> On Sun, 17 Jul 2011 18:24:30 -0400, Andrej Mitrovic
>> <andrej.mitrovich at gmail.com> wrote:
>>
>>> On 7/17/11, Lars T. Kyllingstad <public at kyllingen.nospamnet> wrote:
>>>> - Should I add toNativePath(), which replaces '/' with '\' on Windows
>>>> and
>>>> vice versa on POSIX?
>>>
>>> Actually I withdraw that feature request. Some tools will work with
>>> only forward slashes, others only backward slashes, but this is
>>> regardless of what platform they're on.
>>>
>>> E.g. some tools don't work with forward slashes, while GIT doesn't work
>>> with backward slashes when running on Windows.
>>>
>>> I think .replace(r"\", "/") and .replace("/", r"\") are good enough,
>>> but maybe an alias to each version wouldn't be bad. E.g.
>>> "toForwardSlash" and "toBackslash". It's not hard to define this in our
>>> own code, so it's not really a feature request.
>>
>>
>> Hum... I wonder if normalize should do this...
>>
>> Is normalize supposed to create a canonical path?  If so, then this
>> needs to happen.
>
> normalize does this on Windows, where '/' is also a directory separator,
> but not on POSIX, where '\' is an ordinary filename character.
>
> I am not entirely sure what the exact definition of "canonical path" is,
> but according to some it entails resolving symlinks.  normalize does not
> do this, but it does everything else:
>
>   - resolves . and .. to the extent possible
>   - collapses redundant directory separators
>   - changes '/' to '\' on Windows

OK, this is what I meant.  By canonical path, I mean I should be able to  
take two paths that point to the same filename and normalize should output  
the same string for both.

I agree that the posix version should not replace \ with /, since that's a  
Windows specific issue.

I realize there are some limitations when all you are doing is string  
manipulation.  For example ~steves/blah resolves to the canonical path  
/home/steves/blah.  Same thing with symlinks.

I guess normalize is the best term for it, don't want to confuse it with  
full canonical.

-Steve