Regex match exact number of letters

Question

Let\'s say I want to find all words in which letter \"e\" appears exactly two times. When I define this pattern:

pattern1 <- \"e.*e\" 
grep(pattern1, stri         


        

Answer 1

If you're okay not using grep

stringr::str_count(words, "e") == 2

If you want more efficiency,

stringi::stri_count_fixed(words, "e") == 2

Both of these return logical vectors, you can get the words with words[..code from above..]