Drop-in replacement for grep

[Robinlovelace]

I assume there's a good reason why this seems not to have been done. However, I can't see it and think it would make it easier for people used to base regex to switch. str_which() could be a good option. Could put in a PR but wanted to check if this is something that would be useful.

grep("z", letters)
## [1] 26

 which(str_detect(letters, "z"))
## [1] 26

Context:

http://stackoverflow.com/questions/37996050/stringr-equivalent-to-grep/38012671?noredirect=1#comment66496080_38012671

csgillespie/efficientR@53c9643

[hadley]

Why do you want indices though? I think it's usually a mistake to want them, and in general, you're better off making it explicit by using which (although str_which() might possible be a good name)

[hadley]

@gagolews there's no existing equivalent of this in stringi, right?

[Robinlovelace]

Just for ease of use on the UI - many people discover grep() before they discover grepl() (based on my own experience and teaching). So I think a drop-in replacement would be used, especially by beginners. Just a use-ability thing and totally agree non indexed version is generally better.

[gagolews]

@hadley it's on a to-do list, gagolews/stringi#90

[Robinlovelace]

Thanks!