R/hi.R

In jtvanleuven/snowfall: What the Package Does

#' Start a conversation
#'
#' This function is good. Says hi to someone.
#'
#' @param who character(1) Name of a person.
#' @param how character(1) (optional). How greeting will is given. Options include "shout","whisper","asis"
#' @return A character(1) vector containing the appropriate greeting
#' @examples
#' hi("jt")
#' \dontrun{  #may also use dont test
#'   hi("jt",how="whisper")
#'   }
#' @export


hi <- function(who,how=c("shout","whisper","asis")) {
  stopifnot(is_scalar_character(who))

  how <- match.arg(how)

  fun <- switch(how,
      shout=toupper, whisper=tolower, asis=identity
  )

  paste("hi",fun(who),"how are you?")
}

is_scalar_character <- function(x) {
  is.character(x) &&
  length(x) == 1 &&
  !anyNA(x) &&
  nzchar(x)
}