unique-combinations.R

library(dplyr)

c_sort_collapse <- function(...){
  c(...) %>% 
    sort() %>% 
    paste(collapse = ".")
}

unique_combs <- function(...){
  list(...) %>% 
    purrr::pmap_chr(c_sort_collapse) %>% 
    unique()
}

unique_combs(c("a", "b", "a"), c("a", "a", "b"))