Creating custom R package with data.table custom function

Question

I wanted to create a package following these very clear and simple instructions, https://hilaryparker.com/2014/04/29/writing-an-r-package-from-scratch/ However the following function works when it is not inside a package, but does not work when in a package.

To reproduce this, run the following command in your default folder:Step 1

library("devtools")
library(roxygen2)
create_package("poweR")

This will take you to a new window and in that window: Step 2

exploit_url.R: Create and Copy this to R folder of package

#' @import data.table
exploit_url <- function(df, href, target, anchor, new_col) {
  return(df[, (new_col) := paste0("<a href='", df[[href]], "' target='", target, "'>", df[[anchor]], "</a>", "<br>")][, c(1, 3:6, 8)])
}

Then run the following commands after creating and copying/saving file to R folder of package:

library(devtools)
use_package("data.table")
document()
build()
install()

Close that window and go back to window Step 1

library("poweR")
library(data.table)
DT <- structure(list(cveid = c("CVE-2008-4726", "CVE-2018-18798", "CVE-2001-0791", 
                             "CVE-2005-1823"), EDB_ID = c("6804", "45727", "20893", "25766"
                             ), Type = c("remote", "webapps", "remote", "webapps"), 
                   Platform = c("Windows","PHP", "Windows", "PHP"), 
                   E_DB_Verified = c("Verified", "Waiting verification", "Verified", "Verified"), 
                   E_DB_Published = c("2008-10-22", "2018-10-29", "2001-05-24", "2005-05-30"), 
                   url = c("https://www.exploit-db.com/exploits/6804/","https://www.exploit-db.com/exploits/45727/", 
                           "https://www.exploit-db.com/exploits/20893/", "https://www.exploit-db.com/exploits/25766/")), 
                   class = c("data.table", "data.frame"), row.names = c(NA, -4L))


DT <- exploit_url(DT, "url", '_blank', "E_DB_Verified", "exploitdburl")

I get the following error:

Error in exploit_url(DT, "url", "_blank", "E_DB_Verified", "exploitdburl") : 
  could not find function "exploit_url" 

Is there something I am missing? Any suggestions will be welcome

Answer 1

Solved it based on comments from @jangorecki.