R/appendString.R

In Sumpfohreule/MyUtilities: Collection of general functions which are useful in multiple contexts

#' Appending a string with separator if needed
#'
#' Appending string to a source and seperating both with a separator.
#' If the source is empty the separator is ignored.
#'
#' @param source.string The source value to which to append to. If it is NA or
#' empty sep will be ignored.
#' @param append.string The string which is to be appended to the source. If
#' source is empty only this string is returned
#' @param sep The seperator which is pasted between both strings
#' @export
#' @examples
#' appendString("", "Hello")
#' # "Hello
#'
#' appendString(NA, "Hello")
#' # "Hello"
#'
#' appendString("Hi", "Hello")
#' # "Hi; Hello"
#'
appendString <- function(source.string, append.string, sep = "; ") {
  if (is.na(source.string) | nchar(source.string) == 0) {
    return(append.string)
  } else {
    return(paste(source.string, append.string, sep = sep))
  }
}