[Python-Dev] str object going in Py3K

[Walter Dörwald]

Guido van Rossum wrote:

> On 2/16/06, M.-A. Lemburg <mal at egenix.com> wrote:
>> What will be the explicit way to open a file in bytes mode
>> and in text mode (I for one would like to move away from
>> open() completely as well) ?
>>
>> Will we have a single file type with two different modes
>> or two different types ?
> 
> I'm currently thinking of an I/O stack somewhat like Java's. At the
> bottom there's a class that lets you do raw unbuffered reads and
> writes (and seek/tell) on binary files using bytes arrays. We can
> layer onto this buffering, text encoding/decoding, and more.  (Windows
> CRLF<->LF conversion is also an encoding of sorts).
> 
> Years ago I wrote a prototype; checkout sandbox/sio/.

However sio.DecodingInputFilter and sio.EncodingOutputFilter don't work 
for encodings that need state (e.g. when reading/writing UTF-16). 
Switching to stateful encoders/decoders isn't so easy, because the 
stateful codecs require a stream-API, which brings in a whole bunch of 
other functionality (readline() etc.), which we'd probably like to keep 
separate. I have a patch (http://bugs.python.org/1101097) that should 
fix this problem (at least for all codecs derived from 
codecs.StreamReader/codecs.StreamWriter). Additionally it would make 
stateful codecs more useful in the context for iterators/generators.

I'd like this patch to go into 2.5.

Bye,
    Walter Dörwald