R/haltifnot.R

In ribiosUtils: Utilities from and Interface to the Bioinfo-C (BIOS) Library

#' Ensure the Truth of R Expressions and Print Defined Error Message if NOT
#' 
#' If any of the expressions in \sQuote{...} are not \emph{all} \emph{TRUE},
#' \emph{stop} is called, producing an error message defined by the \emph{msg}
#' parameter.
#' 
#' The function is adapted from the \code{stopifnot} function, with the
#' difference that the error message can be defined the programmer. With
#' \code{haltifnot} error message can be more informative, which is desired for
#' diagnostic and user-interation purposes.
#' 
#' @param \dots any number of \sQuote{logical} R expressions, which should
#' evaluate to \code{TRUE}
#' @param msg Error message.
#' @return \code{NULL} if all statements in \code{...} are \code{TRUE}
#' @author Jitao David Zhang <jitao_david.zhang@@roche.com>
#' @seealso \code{\link{stop}}, \code{\link{warning}} and
#' \code{\link{stopifnot}}
#' @examples
#' 
#' haltifnot(1==1, all.equal(pi, 3.14159265), 1<2) ## all TRUE
#' m <- matrix(c(1,3,3,1), 2,2)
#' haltifnot(m == t(m), diag(m) == rep(1,2)) ## all TRUE
#' 
#' op <- options(error = expression(NULL))
#' # "disable stop(.)"  << Use with CARE! >>
#'      
#' haltifnot(all.equal(pi, 3.141593),  2 < 2, all(1:10 < 12), "a" < "b",
#'           msg="not all conditions are TRUE. Please contact the devleoper")
#' options(op)# revert to previous error handler
#' 
#' @export haltifnot
haltifnot <- function(...,
                      msg="Error undefined. Please contact the developer") {
  n <- length(ll <- list(...))
  if (n == 0L)
    return(invisible())
  mc <- match.call()
  for (i in 1L:n) if (!(is.logical(r <- ll[[i]]) && !any(is.na(r)) &&
                        all(r))) {
    ch <- deparse(mc[[i + 1]], width.cutoff = 60L)
    if (length(ch) > 1L)
      ch <- paste(ch[1L], "....")
    stop(msg, call. = FALSE)
  }
  invisible()
}