[Python-Dev] Pathlib enhancments - method name only

[Eric Snow]

On Fri, Apr 8, 2016 at 3:57 PM, Eric Snow <ericsnowcurrently at gmail.com> wrote:
> On Fri, Apr 8, 2016 at 12:25 PM, Brett Cannon <brett at python.org> wrote:
>> I personally still like __ospath__ as well.
>
> Same here.  The strings are essentially an OS-dependent serialization,
> rather than related to a particular file system.

Hmm.  It's important to note the distinction between a standardized
representation of a path and the OS-dependent representation.  That is
essentially the same distinction as provided by Go's "path" vs.
"path/fliepath" packages.  pathlib provides an abstraction of FS
paths, but does it provide a standardized representation?  From what I
can tell you only ever get some OS-dependent representation.

All this matters because it impacts the value returned from
__ospath__().  Should it return the string representation of the path
for the current OS or some standardized representation?  I'd expect
the former.  However, if that is the expectation then something like
pathlib.PureWindowsPath will give you the wrong thing if your current
OS is linux.  pathlib.PureWindowsPath.__ospath__() would have to fail
or first internally convert to pathlib.PurePosixPath?

On the other hand, it seems like the caller should be in charge of
deciding the required meaning.  That implies that returning a
standardized representation or even something like a
pathlib.PureGenericPath would be more appropriate.

-eric