R/example_model.R

In OncoBayes2: Bayesian Logistic Regression for Oncology Dose-Escalation Trials

#' Runs example models
#'
#' @param topic example to run
#' @param envir environment which the example is loaded into. Defaults
#'     to the caller environment.
#' @param silent logical controlling if execution is run silently
#'     (defaults to \code{FALSE})
#'
#' @return When topic is not specified a list of all possible topics
#'     is return. Whenever a valid topic is specified, the function
#'     inserts the example into the environment given and returns
#'     (invisibly) the updated environment.
#'
#' @template start-example
#' @examples
#'
#' ## get a list of available examples
#' example_model()
#'
#' ## run 3 component example
#' example_model("combo3")
#'
#' @template stop-example
#'
#' @export
example_model <- function(topic, envir = parent.frame(), silent = FALSE) {
  if (missing(topic)) {
    return(names(example_cache))
  }
  assert_character(topic)
  assert_that(
    topic %in% names(example_cache),
    msg = "Unkown example. For a list of examples call example_model()."
  )
  ex_str <- example_cache[[topic]]
  if (silent) {
    ex_str <- c("suppressMessages(capture.output({ ", ex_str, "}))")
    eval(parse(text = ex_str), envir = envir)
  } else {
    message("Running ", topic, " example:\n")
    message(paste(c(ex_str, ""), collapse = "\n"))
    eval(parse(text = ex_str), envir = envir)
  }
  invisible(envir)
}