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Groups > comp.lang.python > #21407

RE: "Decoding unicode is not supported" in unusual situation

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>     Right. The real problem is that Python 2.7 doesn't have distinct
> "str" and "bytes" types.  type(bytes() returns <type 'str'>
> "str" is assumed to be ASCII 0..127, but that's not enforced.
> "bytes" and "str" should have been distinct types, but
> that would have broken much old code.  If they were distinct, then
> constructors could distinguish between string type conversion
> (which requires no encoding information) and byte stream decoding.
> 
>     So it's possible to get junk characters in a "str", and they
> won't convert to Unicode.  I've had this happen with databases which
> were supposed to be ASCII, but occasionally a non-ASCII character
> would slip through.

bytes and str are just aliases for each other. 

>>> id( bytes )
505366496
>>> id( str )
505366496
>>> type( bytes )
<type 'type'>
>>> type( str )
<type 'type'>
>>> bytes == str 
True
>>> bytes is str
True


And I do not think they were ever intended to be just 
ASCII because chr() takes 0 - 256 (non-inclusive) and 
returns a str.


Ramit


Ramit Prasad | JPMorgan Chase Investment Bank | Currencies Technology
712 Main Street | Houston, TX 77002
work phone: 713 - 216 - 5423

--


> -----Original Message-----
> From: python-list-bounces+ramit.prasad=jpmorgan.com@python.org
> [mailto:python-list-bounces+ramit.prasad=jpmorgan.com@python.org] On Behalf
> Of John Nagle
> Sent: Thursday, March 08, 2012 4:24 PM
> To: python-list@python.org
> Subject: Re: "Decoding unicode is not supported" in unusual situation
> 
> On 3/7/2012 6:18 PM, Ben Finney wrote:
> > Steven D'Aprano<steve+comp.lang.python@pearwood.info>  writes:
> >
> >> On Thu, 08 Mar 2012 08:48:58 +1100, Ben Finney wrote:
> >>> I think that's a Python bug. If the latter succeeds as a no-op, the
> >>> former should also succeed as a no-op. Neither should ever get any
> >>> errors when ‘s’ is a ‘unicode’ object already.
> >>
> >> No. The semantics of the unicode function (technically: a type
> >> constructor) are well-defined, and there are two distinct behaviours:
> 
> 
>     This is all different in Python 3.x, where "str" is Unicode and
> "bytes" really are a distinct type.
> 
> 				John Nagle
> --
> http://mail.python.org/mailman/listinfo/python-list

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Thread

"Decoding unicode is not supported" in unusual situation John Nagle <nagle@animats.com> - 2012-03-07 00:25 -0800
  Re: "Decoding unicode is not supported" in unusual situation deets@web.de (Diez B. Roggisch) - 2012-03-07 11:20 +0100
    Re: "Decoding unicode is not supported" in unusual situation Ben Finney <ben+python@benfinney.id.au> - 2012-03-07 22:18 +1100
      Re: "Decoding unicode is not supported" in unusual situation Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-03-07 11:42 +0000
        Re: "Decoding unicode is not supported" in unusual situation John Nagle <nagle@animats.com> - 2012-03-07 11:25 -0800
          Re: "Decoding unicode is not supported" in unusual situation Ben Finney <ben+python@benfinney.id.au> - 2012-03-08 08:48 +1100
            Re: "Decoding unicode is not supported" in unusual situation Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-03-07 23:26 +0000
              Re: "Decoding unicode is not supported" in unusual situation Terry Reedy <tjreedy@udel.edu> - 2012-03-07 19:03 -0500
              Re: "Decoding unicode is not supported" in unusual situation Ben Finney <ben+python@benfinney.id.au> - 2012-03-08 13:18 +1100
                Re: "Decoding unicode is not supported" in unusual situation John Nagle <nagle@animats.com> - 2012-03-08 14:23 -0800
                RE: "Decoding unicode is not supported" in unusual situation "Prasad, Ramit" <ramit.prasad@jpmorgan.com> - 2012-03-08 22:58 +0000
                Re: "Decoding unicode is not supported" in unusual situation John Nagle <nagle@animats.com> - 2012-03-09 10:11 -0800
                Re: "Decoding unicode is not supported" in unusual situation Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-03-10 00:57 +0000
                Re: "Decoding unicode is not supported" in unusual situation John Nagle <nagle@animats.com> - 2012-03-10 22:12 -0800
                Re: "Decoding unicode is not supported" in unusual situation Neil Cerutti <neilc@norwich.edu> - 2012-03-09 13:23 +0000

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