How to escape closed bracket “]” in regex in R

Question

I\'m trying to use gsub in R to replace a bunch of weird characters in some strings I\'m processing. Everything works, except whenever I throw in \"]\" it make

Answer 1

You can switch the order of the character class without escaping.

name <- 'R U Still Down? [Remember Me][*[[]*'
gsub('[][?*]', '', name)
# [1] "R U Still Down Remember Me"

If you want to remove all punctuation characters, use the POSIX class [:punct:]

gsub('[[:punct:]]', '', name)

This class in the ASCII range matches all non-controls, non-alphanumeric, non-space characters.

ascii <- rawToChar(as.raw(0:127), multiple=T)
paste(ascii[grepl('[[:punct:]]', ascii)], collapse="")
# [1] "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~"

Answer 2

Just enable perl=TRUE parameter.

> gsub("[?\\]\\[*]", "", name, perl=T)
[1] "R U Still Down Remember Me"

And escape only the needed characters.

> gsub("[()*$+?'\\[\\]]", "", name, perl=T)
[1] "R U Still Down Remember Me"