R/checkArg.R

In ManonMartin/PAMMULAD:

checkArg <- function(arg, checks, can.be.null = FALSE) {
  check.list <- list(bool = c(is.logical, "a boolean"),
                     int = c(function(x) {x%%1 == 0}, "an integer"),
                     num = c(is.numeric, "a numeric"),
                     str = c(is.character, "a string"),
                    pos = c(function(x) {x > 0 }, "positive"),
                    pos0 = c(function(x) {x >= 0}, "positive or zero"))

  if (is.null(arg))  {
    if (!can.be.null)  {
      stop(deparse(substitute(arg)), " is null.")
    }
  } else  {
    if (is.matrix(arg)) {
      stop(deparse(substitute(arg)), " is not scalar.")
    }
    for (c in checks) {
      if (!check.list[[c]][[1]](arg)) {
        stop(deparse(substitute(arg)), " is not ", check.list[[c]][[2]],".")
      }
    }
  }
}