R/showSlotInfo.R

In acidgenomics/AcidBase: Acid Genomics Base Functions

#' Show slot information
#'
#' @export
#' @note Updated 2023-09-21.
#'
#' @details
#' Standardized to Bioconductor `show()` method conventions.
#' Refer to `SummarizedExperiment` method for example.
#'
#' @param list `list`.
#' Named list containing slot metadata.
#'
#' @return Console output, via [cat()].
#'
#' @examples
#' showSlotInfo(list(
#'     dir = "~",
#'     skip = NULL,
#'     filtered = TRUE
#' ))
showSlotInfo <- function(list) {
    assert(is.list(list))
    list <- Filter(f = Negate(is.null), x = list)
    list <- Filter(f = hasLength, x = list)
    out <- unlist(Map(
        f = function(name, x) {
            if (length(x) == 1L) {
                paste0(name, ": ", x)
            } else {
                if (hasNames(x) && length(x) <= 4L) {
                    prefix <- paste0("[", names(x), "]")
                    info <- paste(prefix, x, sep = " ", collapse = "; ")
                } else {
                    info <- headtail(x)
                }
                paste0(name, "(", length(x), "): ", info)
            }
        },
        name = names(list),
        x = list,
        USE.NAMES = FALSE
    ))
    cat(out, sep = "\n")
    invisible(NULL)
}