r - Remove single backslash

Question

I have a string with backslash and I want to remove them.

test = "m \"#\""

Have tried the following but none works :

gsub( "\\\\", "", test )
gsub( "\\\\", "", test, fixed = T )
gsub( "\\", "", test )
gsub( "\\", "", test, fixed = T )

Have looked into similar questions but none of the solutions work.

Replace single backslash in R Remove Single Backslash String R

Edit : Actually this text is going to be passed in system() function to run a mosquitto client. User will give various parameters as input and the command will be created up on the fly.

The full command looks like this : mosquitto_sub -h test.mosquitto.org -q 0 -k 60 -t \\"#\\"

However it is expected to be like this : mosquitto_sub -h test.mosquitto.org -q 0 -k 60 -t "#"

Otherwise system() does not take it. Hence is the requirement to remove the backslaches.

The parameters 0 and 60 and # are supplied by user. Hence using paste0() to make this string. After the string is created the backslashes comes up.

The string given in text here is to create a reproducible and short example here.

Answer 1

There is no backslash in your string

grepl("\\", test, fixed = TRUE)
# FALSE

Answer 2

I think JvdV is right, I don't think the string "m "#"" can exist within R without the backslashes. The backslash makes " and # characters rather than acting as open/close quotation marks and a comment mark respectively. If you had """" you'd get an error as you have a set of quotation marks within another set which is not possible. The same might occur for "m "#"" . However if you input "m "#"" the hash acts a comment symbol, making everything after it a comment and you get "m " . You need backslashes to make " not a quotation mark but a character, and # not a comment symbol but a character.