I'm trying to get better at using Emacs regular expressions. Reading the documentation I see:
matches any character that belongs to the category C. For example, ‘\cc’ matches Chinese characters, ‘\cg’ matches Greek characters, etc. For the description of the known categories, type
‘M-x describe-categories <RET>’.
If I run
describe-categories I see:
Legend of category mnemonics (longer descriptions at the bottom) :space for indent 9:semivowel lower R:Right-to-left ... k:Katakana .:Base <:Not at eol Y:2-byte Cyrillic l:Latin 0:consonant >:Not at bol ^:Combining o:Lao 1:base vowel A:2-byte alnum a:ASCII q:Tibetan 2:upper diacritic C:2-byte han b:Arabic r:Roman 3:lower diacritic G:2-byte Greek c:Chinese t:Thai 4:combining tone H:2-byte Hiragana e:Ethiopic v:Viet 5:symbol I:Indian Glyphs g:Greek w:Hebrew 6:digit K:2-byte Katakana h:Korean y:Cyrillic ...
Isn't that first item the space character? But if run
isearch-forward-regexp and try
\c , it finds nothing, even in a buffer with lots of whitespace. Trying
\c6 to find digits also doesn't work.
Are these bugs or am I using it wrong?
I'm using GNU Emacs 27.2 on macOS.