R exact match for multiple patterns

Question

I would like to find exact matches for "A1" and "A6" in the vector:

myfile=paste("A",c(1:10),sep="")

I used str_detect from the stringr package:

toMatch <- c("A1", "A6")


str_detect(myfile,fixed(paste(toMatch,collapse="|")))

but it returns TRUE also for partial match with "A10".

Any other funs that could work?

user_3732271 · Answer

We could use the word boundary (\b) to avoid the unnecessary partial matches

str_detect(myfile,paste0("\b(", paste(toMatch, collapse="|"), ")\b"))
 [1]  TRUE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE

Based on the elements used, it can be done with %in%

myfile %in% toMatch
1]  TRUE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE