Complete word matching using grepl in R

Question

Consider the following example:

> testLines <- c(\"I don\'t want to match this\",\"This is what I want to match\")
> grepl(\'is\',testLines)
> [         


        

Answer 1

"\<" is another escape sequence for the beginning of a word, and "\>" is the end. In R strings you need to double the backslashes, so:

> grepl("\\", c("this", "who is it?", "is it?", "it is!", "iso"))
[1] FALSE  TRUE  TRUE  TRUE FALSE

Note that this matches "is!" but not "iso".