[Python-Dev] What to do for bytes in 2.6?

[Thomas Heller]

Guido van Rossum schrieb:
> I believe the issue of whether and how to backport bytes (and
> bytearray?) from 3.0 to 2.6 has come up before, but I don't think
> we've come to any kind of conclusion. It's quite subtle. In a private
> email, Thomas Wouters and I discussed this:
> 
> [Guido]
>> > Perhaps the biggest question in my mind is what to do with bytes in
>> > 2.6. Make it an alias for str? Or a new type that doesn't mix with
>> > either str or unicode? But then how do we get read() calls and the
>> > like on binary files or sockets to return bytes instances? Perhaps a
>> > trivial str subclass? Or return bytes when -3 is specified? I need to
>> > bring this up on the list.
> 
> [Thomas]
>> I don't know yet. I'm not sure yet what to do with strings and unicode in
>> 2.6 in -3 mode (or perhaps through a future-import, with some hackery.)
>> Perhaps a *set* of str-subclasses makes sense: a will-be-unicode subclass,
>> and a will-be-bytes subclass. String literals and text-mode input would
>> produce will-be-unicode, binary input and byte literals will-be-bytes.
>> Switching between -3 and normal mode for that would be changing a few
>> pointers in the core, making all operations return normal strings in normal
>> mode. And the would-be types can produce whatever warning they wish -- they
>> need not worry about speed. But I'm not sure if that'll work.
> 

Is the bytes type required for PEP3118 'Revising the buffer protocol'?
I just started to work on implementing this PEP for ctypes, in the
hope that these changes can be merged into trunk.

Thomas