How to generate auto-incrementing ID in R

Question

I am looking for an efficient way to create unique, numeric IDs for some synthetic data I\'m generating.

Right now, I simply have a function that emits and incremen

Answer 1

I like to use the proto package for small OO programming. Under the hood, it uses environments in a similar fashion to what Martin Morgan illustrated.

# this defines your class
library(proto)
Counter <- proto(idCounter = 0L)
Counter$emitID <- function(self = .) {
   id <- formatC(self$idCounter, width = 9, flag = 0, format = "d")
   self$idCounter <- self$idCounter + 1L
   return(id)
}

# This creates an instance (or you can use `Counter` directly as a singleton)
mycounter <- Counter$proto()

# use it:
mycounter$emitID()
# [1] "000000000"
mycounter$emitID()
# [1] "000000001"