[Python-Dev] pathlib - current status of discussions

[Ethan Furman]

On 04/14/2016 07:01 AM, Random832 wrote:
> On Thu, Apr 14, 2016, at 09:50, Chris Angelico wrote:
>> Adding integers and floats is considered "safe" because most people's
>> use of floats completely compasses their use of ints. (You'll get
>> OverflowError if it can't be represented.) But float and Decimal are
>> considered "unsafe":
>>
>>--> 1.5 + decimal.Decimal("1.5")
>> Traceback (most recent call last):
>>    File "<stdin>", line 1, in <module>
>> TypeError: unsupported operand type(s) for +: 'float' and
>> 'decimal.Decimal'
>>
>> This is more what's happening here. Floats and Decimals can represent
>> similar sorts of things, but with enough incompatibilities that you
>> can't simply merge them.
>
> And what such incompatibilities exist between bytes and str for the
> purpose of representing file paths? At the end of the day, there's
> exactly one answer to "what file on disk this represents (or would
> represent if it existed)".

Interoperability with other systems and/or libraries.  If we use 
surrogateescape to transform str to bytes, and the other side does not, 
we no longer have a workable path.

--
~Ethan~