I have numerous similar functions where only one or two words need to change in the documentation. To limit duplication, I’m using functions inside the documentation.

This works in roxygen2 for @description and @param, but I cannot get it to work for @examples. The inline code is not evaluated.

Example

useless_description <- function(name) {
  paste0('This useless function prints the word "', name , '" n times.')
}

useless_example <- function(name) {
  paste0("# Print ", name, " 1 time",
         name, "(1)",
         "",
         "# Print ", name, " 3 times",
         name, "(3)",
         sep = "n"
         )
}

#' @title Hello
#' @description `r useless_description("hello")`
#' @examples `r useless_example("hello")`
hello <- function(n) {
  print(rep("hello", n))
}

#' @title Goodbye
#' @description `r useless_description("goodbye")`
#' @examples `r useless_example("hello")`
goodbye <- function(n) {
  print(rep("goodbye", n))
}

When running devtools::document(), this is the help page that is created for the function hello():

Possible solution using @eval

I have found a way around this, but it uses the superseded keyword @eval.

useless_example2 <- function(name) {
  c("@examples ",
    paste0("# Print ", name, " 1 time"),
    paste0(name, "(1)"),
    "",
    paste0("# Print ", name, " 3 time"),
    paste0(name, "(3)")
    )
}

#' @title Hello
#' @description `r useless_description("hello")`
#' @eval useless_example2("hello")
hello <- function(n) {
  print(rep("hello", n))
}

Resulting help page:

Question

Is there a way to evaluate inline code in roxygen2 @examples without using superseded functions?