[Python-Dev] bytes.from_hex()

[Bob Ippolito]

On Feb 19, 2006, at 10:55 AM, Martin v. Löwis wrote:

> Stephen J. Turnbull wrote:
>> BTW, what use cases do you have in mind for Unicode -> Unicode
>> decoding?
>
> I think "rot13" falls into that category: it is a transformation
> on text, not on bytes.

The current implementation is a transformation on bytes, not text.   
Conceptually though, it's a text->text transform.

> For other "odd" cases: "base64" goes Unicode->bytes in the *decode*
> direction, not in the encode direction. Some may argue that base64
> is bytes, not text, but in many applications, you can combine base64
> (or uuencode) with abitrary other text in a single stream. Of course,
> it could be required that you go u.encode("ascii").decode("base64").

I would say that base64 is bytes->bytes.  Just because those bytes  
happen to be in a subset of ASCII, it's still a serialization meant  
for wire transmission.  Sometimes it ends up in unicode (e.g. in  
XML), but that's the exception not the rule.

-bob