R using regexpr, with multiple pattern - regex

Question

I would like to find the string just after some patterns. My code seem to work but I cannot finish the job.
Here is an illustration:
pattern <- c("Iligan", "Cabeseria 25|Sta. Lucia", "Capitol", "Osmeña",
"Nowhere", "Aglayan")
# I want to match the string just after each pattern. For example I'm going to
# match City just after Iligan.
target <-c("Iligan City", "Sta. Lucia, Ozamiz City", " Oroquieta City",
"Osmeña St. Dipolog City", "Lucia St., Zamboanga City",
"Aglayan str, Oroquieta City", "Gingoog City", "Capitol br., Ozamiz City",
"Dumaguete City", "Poblacion, Misamis")
#The matches seems to work fine
(matches <- sapply(pattern,FUN=function(x){regexpr(paste0("
(?<=\\b",x,"\\b ",")","[\\w-*\\.]*"),target,perl=T)}))
print (matches)
#But I cannot get the results. I would need use the column of each matrix
#at a time
villain <- lapply(matches,FUN = function(x)(regmatches(target,x)))
Do you have a solution to this problem.
unpdate 1
For the sake of being precise here is the desired output.
results <- c("City", "St.", "br.")
#[1] "City" "St." "br."

Answer 1

There are some helpers in the stringr package that can simplify the process:
pattern <- c("Iligan", "Cabeseria 25|Sta. Lucia", "Capitol", "Osmeña",
"Nowhere", "Aglayan")
target <-c("Iligan City", "Sta. Lucia, Ozamiz City", " Oroquieta City",
"Osmeña St. Dipolog City", "Lucia St., Zamboanga City",
"Aglayan str, Oroquieta City", "Gingoog City", "Capitol br., Ozamiz City",
"Dumaguete City", "Poblacion, Misamis")
matchPat <- function(x) {
unlist(str_extract(target, perl(paste0("(?<=\\b", x, "\\b ",")","[\\w-*\\.]*"))))
}
matches <- sapply(pattern, matchPat)
print(matches)
## Iligan Cabeseria 25|Sta. Lucia Capitol Osmeña Nowhere Aglayan
## [1,] "City" NA NA NA NA NA
## [2,] NA NA NA NA NA NA
## [3,] NA NA NA NA NA NA
## [4,] NA NA NA "St." NA NA
## [5,] NA NA NA NA NA NA
## [6,] NA NA NA NA NA "str"
## [7,] NA NA NA NA NA NA
## [8,] NA NA "br." NA NA NA
## [9,] NA NA NA NA NA NA
## [10,] NA NA NA NA NA NA
This can be simplified further if you don't need indicators for non-matches, but no sample/expected output was provided.