[Python-3000] [Python-Dev] New proposition for Python3 bytes filename issue

[Terry Reedy]

Martin v. Löwis wrote:
> Guido van Rossum wrote:
>> However
>> the *proposed* behavior (returns bytes if the arg was bytes, and
>> returns str when the arg was str) is IMO sane, and no different than
>> the polymorphism found in len() or many builtin operations.
> 
> My concern still is that it brings the bytes type into the status of
> another character string type, which is really bad, and will require
> further modifications to Python for the lifetime of 3.x.

I am one of those who wanted bytes kept and bytearray added and once 
grumbled about strings becoming unicode.  Now that I am using 3.0 (and 
can imagine future use of non-ascii chars), I appreciate having just one 
string type and a separation between normal text and small-int arrays. 
So I find my self, somewhat surprisingly to me, sharing Martin's concern 
about regression toward having two text types again.

There once was a discussion about whether paths should be represented by 
strings or a separate path class (that would keep a tuple of strings for 
each component).  This was rejected, as I remember, both because of the 
complication/benefit ratio and the anticipation that having just one 
string type would make string representation easier.

Using just 3.0 strings seems not to be possible.  So a different 
argument for a path class would be to encapsulate the implementation, 
which could depend on the OS, and hide the complications from the user, 
who just wants open to work.

Terry Jan Reedy