How to add a missing closing parenthesis to a string in R?-CodePudding

I would like to add a closing parenthesis to strings that have an open parenthesis but are missing a closing parenthesis. For instance, I would like to modify "The dog walked (ABC in the park" to be "The dog walked (ABC) in the park".

I found a similar question and solution but it is in Python (How to add a missing closing parenthesis to a string in Python?). I have tried to modify the code to be used in R but to no avail. Can someone help me with this please?

I have tried modifying the original python solution as R doesn't recognise the "r" and "\" has been replaced by "\\" but this solution doesn't work properly and does not capture the string preceded before the bracket I would like to add:

text = "The dog walked (ABC in the park"
str_replace_all(text, '\\([A-Z] (?!\\))\\b', '\\)') 
text

The python solution that works is as follows:

text = "The dog walked (ABC in the park"
text = re.sub(r'(\([A-Z] (?!\))\b)', r"\1)", text)
print(text)

CodePudding user response：

Try this

stringr::str_replace_all(text, '\\([A-Z] (?!\\))\\b', '\\0\\)')

output

"The dog walked (ABC) in the park"

CodePudding user response：

You might also use gsub, and first use the word boundary and then the negative lookahead.

In the replacement use the first capture group followed by )

text = "The dog walked (ABC in the park"
gsub('(\\([A-Z] )\\b(?!\\))', '\\1\\)', text, perl=T)

Output

[1] "The dog walked (ABC) in the park"

CodePudding user response：

Not a one liner, but it does the trick and is (hopefully!) intuitive.

library(stringr)

add_brackets = function(text) {
    brackets = str_extract(text, "\\([:alpha:] ") # finds the open bracket and any following letters
    brackets_new = paste0(brackets, ")") # adds in the closing brackets
    str_replace(text, paste0("\\", brackets), brackets_new) # replaces the unclosed string with the closed one
}

> add_brackets(text)
[1] "The dog walked (ABC) in the park"