Keyword Searches from Comma Separated Terms

Long story short, I need to convert a pretty simple OR search to a non-directional AND keyword search. Direction is straightforward, with just using [.*?] between words (or in SQL using LIKE keyword_1%keyword_2). Anyhow, I came up with this little function and thought I would share.

keyword_search <- paste0(sapply(unlist(strsplit("keyword_1,keyword_2", ",")),function(x) {
 return(paste0("(?=.*?(",x,"))"))
}),collapse="")

Now this sets keyword_search to a really nice regular expression that can be used with grep.

NOTE: You will need to use PERL = TRUE when using the generated regular expression.

(?=.*?(keyword_1))(?=.*?(keyword_2))

Results from regex101 show the following breakdown for the curious