[Python-3000] PEP 3137: Immutable Bytes and Mutable Buffer

[Gregory P. Smith]

On 9/26/07, Guido van Rossum <guido at python.org> wrote:
> [PEP 3137]
> > > **Open Issue:** I'm undecided on whether indexing bytes and buffer
> > > objects should return small ints (like the bytes type in 3.0a1, and
> > > like lists or array.array('B')), or bytes/buffer objects of length 1
> > > (like the str type).  The latter (str-like) approach will ease porting
> > > code from Python 2.x; but it makes it harder to extract values from a
> > > bytes array.
>
> On 9/26/07, Brett Cannon <brett at python.org> wrote:
> > How much do you care about making the 2 -> 3 transition easy?  If you
> > don't go the str way then comparisons like ``bytes_[0] == b"A"`` won't
> > work unless you allow comparisons between ints and length 1
> > bytes/buffers.  Extracting a single item is not horrendous if you pass
> > it to int().
> >
> > Personally I say go with the list-like semantics.  Having the
> > following code return false seems odd (but not ridiculous) to me::
> >
> >   stuff = bytes([0, 1])
> >   stuff[1] = 42
> >   stuff[1] == 42
> >
> > So unless int comparisons are allowed I am -0 on the str-like semantics.
>
> int comparisons would stick out like a sore thumb, especially since
> they can only be reasonably made to work on 1-byte strings.
>
> I'm still undecided (despite Marcin's eloquent argument for ints as
> bytes) but I'm open for votes for this case.
>

looks like my response in the other thread suggesting allowing
comparisons of len==1 to ints was already mentioned before me.  yay.
I'm +0.5 on the idea of allowing the len==1 to int comparison and
returning ints for the bytes/buffer indices and iteration.

glad to see this as a PEP, it feels more real. :)

-gps