[Python-Dev] [Python-3000] Betas today - I hope

[Walter Dörwald]

M.-A. Lemburg wrote:
> On 2008-06-11 13:35, Barry Warsaw wrote:
>> So I had planned to do a bunch of work last night looking at the 
>> release blocker issues, but nature intervened.  A bunch of severe 
>> thunderstorms knock out my 'net access until this morning.
>>
>> I'll try to find some time during the day to look at the RB issues.  
>> Hopefully we can get Guido to look at them too and Pronounce on some 
>> of them.  Guido please start with:
>>
>> http://bugs.python.org/issue643841
>>
>> My plan is to begin building the betas tonight, at around 9 or 10pm 
>> EDT (0100 to 0200 UTC Thursday).  If a showstopper comes up before 
>> then, I'll email the list.  If you think we really aren't ready for 
>> beta, then I would still like to get a release out today.  In that 
>> case, we'll call it alpha and delay the betas.
> 
> There are two things I'd like to get in to 3.0:
> 
>  * .transform()/.untransform() methods (this is mostly done, just need
>    to add the methods to PyUnicode, PyBytes and PyByteArray)

What would these methods do? Use the codec machinery without any type 
checks?

I think for transformations we don't need the full codec machinery:

We probably don't need extensible error handling.

There are transformation that are not invertible, so it doesn't make 
sense to have both operations in one object. If the operation *is* 
invertible, two tranformers can be used.

Do we really need a registry that maps function named to functions?

A simple API might look like this:

class TransformInfo:
    # stateless transformer
    def transform(self, input):

    # return stateful incremental transformer
    def incrementaltransformer(self):

    # wrap stream in a transforming stream
    def streamtransformer(self, stream):

incrementaltransformer() would return an object that has one method:

    def transform(self, input, final=False);

> [...]

Servus,
    Walter