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

[Ryan Gonzalez]

On October 21, 2015 9:53:05 PM CDT, Yury Selivanov <yselivanov.ml at gmail.com> wrote:
>On 2015-10-21 10:44 PM, Ben Finney wrote:
>>> >In the process, we had to make a decision on how to highlight raw
>>> >string literals -- r''. Many existing highlighters assume that all
>raw
>>> >strings are regexps, and highlight them as such, i.e. '\s' and '\n'
>>> >will be highlighted.
>> That is evidently a simple mistake. Merely knowing that a token is a
>raw
>> string does not justify the assumption that the string is a regular
>> expression, or a filesystem entry name, or a line in a network
>protocol,
>> or anything except plain text.
>
>I agree 100%.
>
>But: github, gitlab, Atom, Sublime Text, and many other tools

GitHub and Atom both use language-python.

>assume that raw strings (with lowercase r) are regexps.  If you
>don't highlight them as such, people think that it's a bug.
>
>Since I wanted MagicPython to be a drop-in replacement for
>standard highlighters, I simply *could not* change this
>behavior.  It's already a standard of some sorts, whether we
>like it or not.
>
>> Perhaps some more explicit context could be used to signal what the
>> intent of a raw string is, but you'd need to find a strong consensus
>> that programmers actually intend that. “It's a raw string” doesn't
>> justify any of those assumptions.
>>
>
>If we want to design some special marker for highlighters to
>hint what language is in the string, I'd strongly suggest that
>it should be before the string literal.  For instance, it
>*won't* be possible for most highlighters to detect this:
>
>    my_re = '''...
>    ...''' # regex
>
>Yury
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