Re: Correct syntax for pathological re.search()

On 2024-10-19 00:15:23 +0200, jak via Python-list wrote:

Peter J. Holzer ha scritto:

As a trivial example, the regular expressions r"\sout{" and r"\sout\{"
are equivalent (the \ before the { is redundant). Yet
re.compile(s).pattern preserves the difference between the two strings.

 
Allow me to be fussy: r"\sout{" and r"\sout\{" are similar but not
equivalent.

They are. Both will match the 6 character string
    0005c \ REVERSE SOLIDUS
    00073 s LATIN SMALL LETTER S
    0006f o LATIN SMALL LETTER O
    00075 u LATIN SMALL LETTER U
    00074 t LATIN SMALL LETTER T
    0007b { LEFT CURLY BRACKET

If you omit the backslash, the parser will have to determine if the
graph is part of regular expression {n, m} and will take more time.

Yes, that's the parser. But the result of parsing will be the same:
The string will end in a literal backslash.

        hp

--
   _  | Peter J. Holzer    | Story must make more sense than reality.
|_|_) |                    |
| |   | hjp@hjp.at         |    -- Charles Stross, "Creative writing
__/   | http://www.hjp.at/ |       challenge!"