Files
shiny/R/cache-utils.R
2018-06-28 23:58:55 -05:00

29 lines
571 B
R

#' A Key Missing object
#'
#' A \code{key_missing} object represents a cache miss.
#'
#' @seealso \code{\link{diskCache}}, \code{\link{memoryCache}}.
#'
#' @export
key_missing <- function() {
structure(list(), class = "key_missing")
}
#' @rdname key_missing
#' @export
is.key_missing <- function(x) {
inherits(x, "key_missing")
}
#' @export
print.key_missing <- function(x, ...) {
cat("<Key Missing>\n")
}
validate_key <- function(key) {
if (grepl("[^a-z0-9]", key)) {
stop("Invalid key: ", key, ". Only lowercase letters and numbers are allowed.")
}
}