regex - Strange regular expression string -


this question has answer here:

when learn gnu emacs lisp, confused code.

(looking-back "\\s)" 1)

i don't know \\s) stand for?i know can mach character ), , want know rule of matching string. why not use regular expression?

"i don't know \\s) stand for? know can mach character ), , want know rule of matching string."

\s) matches 1 occurrence of character syntax class "close parenthesis".

see elisp manual, node syntax class table.

open parenthesis characters: (

close parenthesis characters: )

characters used in dissimilar pairs surround sentences or expressions. such grouping begun open parenthesis character , terminated close. each open parenthesis character matches particular close parenthesis character, , vice versa. normally, emacs indicates momentarily matching open parenthesis when insert close parenthesis. *note blinking::.

in human languages, , in c code, parenthesis pairs (), [], , {}. in emacs lisp, delimiters lists , vectors (() , []) classified parenthesis characters.


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