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Re: Is It Bug?

References <27c0b454-62e9-410f-b05c-7c5fe306f8aa@googlegroups.com> <mailman.3713.1386464744.18130.python-list@python.org> <roy-756493.20224107122013@news.panix.com> <CAMw+j7JEEbj6Pt-ZGPT9dniyzokOKGvFd6ttTSDF9m5JO=GPfQ@mail.gmail.com>
Date 2013-12-08 21:26 +1100
Subject Re: Is It Bug?
From Chris Angelico <rosuav@gmail.com>
Newsgroups comp.lang.python
Message-ID <mailman.3722.1386498404.18130.python-list@python.org> (permalink)

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On Sun, Dec 8, 2013 at 9:01 PM, Chris “Kwpolska” Warrick
<kwpolska@gmail.com> wrote:
> A raw string cannot end with a backslash.
>
>>>> r'a\a'
> 'a\\a'
>>>> r'a\'
>   File "<stdin>", line 1
>     r'a\'
>         ^
> SyntaxError: EOL while scanning string literal

Incidentally, the solution to this would be to not use the backslash
to escape the quote. That's what introduces the ambiguity. Instead, a
raw literal could do as REXX does and double the quote to escape it.
(Any whitespace and it's still concatenation as normal. I'm not
advocating REXX's handling there.)

>>> r"asdf""qwer"
'asdfqwer'

If we had a new "pure string" that worked thus:
>>> p"asdf""qwer"
'asdf"qwer'

>>> p"\b""\d+""\b"
'\\b"\\d+"\\b'

which would be a regex matching quoted strings of digits. The only
potential ambiguity would be in that closing the quote and opening
another would normally revert to a regular string literal, where by
this model it's still a pure string. Editor lexers would have to
understand that.

ChrisA

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Thread

Is It Bug? Mahan Marwat <mahanmarwat@gmail.com> - 2013-12-07 16:59 -0800
  Re: Is It Bug? Chris Angelico <rosuav@gmail.com> - 2013-12-08 12:05 +1100
    Re: Is It Bug? Roy Smith <roy@panix.com> - 2013-12-07 20:22 -0500
      Re: Is It Bug? Chris “Kwpolska” Warrick <kwpolska@gmail.com> - 2013-12-08 11:01 +0100
      Re: Is It Bug? Chris Angelico <rosuav@gmail.com> - 2013-12-08 21:04 +1100
      Re: Is It Bug? Chris Angelico <rosuav@gmail.com> - 2013-12-08 21:26 +1100
  Re: Is It Bug? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-12-08 01:06 +0000
  Re: Is It Bug? MRAB <python@mrabarnett.plus.com> - 2013-12-08 01:12 +0000
  Re: Is It Bug? Tim Roberts <timr@probo.com> - 2013-12-07 22:53 -0800
  Re: Is It Bug? Peter Otten <__peter__@web.de> - 2013-12-08 11:43 +0100

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