Combining with stringr functions

You can pass a regular expression as the pattern argument to any stringr function that has the pattern argument. You can use str_detect() to get a logical vector for whether there was a match, str_subset() to return just the strings with matches, and str_count() to count the number of matches in each string.

As a reminder, compare the output of those three functions with our "c_t" pattern from the previous exercise:

x <- c("cat", "coat", "scotland", "tic toc")
pattern <- "c" %R% ANY_CHAR %R% "t"
str_detect(x, pattern)
str_subset(x, pattern)
str_count(x, pattern)

It now also makes sense to add str_extract() to your repertoire. It returns just the part of the string that matched the pattern:

str_extract(x, pattern)

You'll combine your regular expression skills with stringr to ask how often a q is followed by any character in boy names.

It's always a good idea to test your pattern, so this pattern is shown matched with four names. The first two shouldn't have matches (can you explain why?) but the last two should.