[Python-ideas] PEP 8: raw strings & regular expressions

[Sven R. Kunze]

I think you shouldn't push it, Yury.

Most people here seem not to like it that much for many reasons.

Best,
Sven

On 23.10.2015 00:56, Yury Selivanov wrote:
> Hi Barry,
>
> On 2015-10-22 5:17 PM, Barry Warsaw wrote:
>>> I think that it might be a good idea to state the following in PEP 8:
>>> >
>>> >- use r'...' strings for raw strings that describe regular 
>>> expressions;
>>> >these strings might be highlighted specially in some editors.
>>> >
>>> >- use R'...' strings for raw strings; editors*should not* highlight
>>> >any escaped characters in them.
>> Aside from other comments in this thread, I think it's generally a 
>> bad idea to
>> codify semantics where there are none defined by the language. So r'' 
>> and R''
>> are equivalent.  It would be like assigning different semantics or 
>> syntax
>> highlighting for 'foo' and "foo".
>
> The thing is that *a lot* of Python users have already made
> the choice -- many tools (including GitHub) do highlight
> r'' strings as regexps, and people love this feature, and
> complain when it's not implemented in their tool of choice.
> This is an extremely useful feature, since any regexp longer
> than 20 characters is unreadable at a glance.
>
> On the other hand, *a lot* of users are annoyed, when their
> raw strings are highlighted as regexps (why \n is highlighted
> as escaped?).  Often that results not in just wrongly
> highlighted raw strings, but in broken highlighting of
> the whole source file [1].
>
> In principle, there is no reason why *both* of these groups
> of users can't use one tool and be happy.  I propose to
> establish a convention in PEP 8, explaining that, while both
> literals are semantically equivalent,
>
> - r'..' strings *should* be used for regexps,
>
> - R'..' strings *should* be used for unstyled raw strings,
>
> and tools *should* treat them as such.
>
> All of this is merely about codifying the current status quo.
>
> Thanks,
> Yury
>
>
> [1] https://gist.github.com/1st1/d3da5d69a9b6c088c26f
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