Обсуждение: \W excludes underscore
Table 9.19. Regular Expression Class-shorthand Escape:
> \w [[:alnum:]_] (note underscore is included)
> ...
> \W [^[:alnum:]_] (note underscore is included)
This is misleading as \w *includes* underscore, but \W *excludes* it. I suggest:
\w [[:alnum:]_] (underscore is included)
...
\W [^[:alnum:]_] (underscore is excluded)
Regards
Erwin
On Tue, May 7, 2019 at 4:36 PM Erwin Brandstetter <brsaweda@gmail.com> wrote:
Table 9.19. Regular Expression Class-shorthand Escape:> \w [[:alnum:]_] (note underscore is included)> ...> \W [^[:alnum:]_] (note underscore is included)This is misleading as \w *includes* underscore, but \W *excludes* it. I suggest:
Its saying that the underscore is one of the characters that is included in the exclusion, alongside the alphabetical characters.
\w [[:alnum:]_] (underscore is included)...\W [^[:alnum:]_] (underscore is excluded)
Or just "note the underscore"
The reader is already assumed to know that the capital letters and the leading ^ in the bracket denote exclusion since its doesn't call out that specifically.
David J.