# sfmisc utils 0.0.1.9025
# utils -------------------------------------------------------------------
# nocov start
# commonly used utility functions included from the package sfmisc
#' Paste and Truncate
#'
#' @param x a vector
#' @param width (maximum) width of result
#' @param dots `character` scalar. String to use for ellipses
#' @inheritParams paste
#'
#' @return a `character` scalar
#' @noRd
ptrunc <- function(
...,
width = 40L,
sep = ", ",
collapse = ", ",
dots = " ..."
){
assert(width > 7L, "The minimum supported width is 8")
x <- paste(..., sep = sep, collapse = collapse)
sel <- vapply(x, nchar, integer(1), USE.NAMES = FALSE) > width
x[sel] <- strtrim(x[sel], width = width - 4L)
x[sel] <- paste0(gsub(",{0,1}\\s*$", "", x[sel]), dots)
x
}
fmt_class <- function(x){
paste0("<", paste(x, collapse = "/"), ">")
}
#' @param x any \R object
#' @param ignore subclasses to ignore
#' @noRd
class_fmt <- function(x, ignore = NULL){
fmt_class(setdiff(class(x), ignore))
}
compact <- function(x){
x[!vapply(x, is.null, FALSE)]
}
walk <- function(.x, .f, ...){
for (i in seq_along(.x)){
.f(.x[[i]], ...)
}
invisible(.x)
}
# assertions --------------------------------------------------------------
#' Assert a condition
#'
#' A simpler and more efficient for [base::stopifnot()] that has an easy
#' mechanism for supplying custom error messages. As opposed to `stopifnot()`,
#' `assert()` only works with a single (scalar) assertions.
#'
#' @param cond `TRUE` or `FALSE` (without any attributes). `FALSE` will throw
#' an exception with an automatically constructed error message (if `...`
#' was not supplied). Anything else will throw an exception stating that
#' `cond` was not valid.
#' @param ... passed on to [stop()]
#' @param call. passed on to [stop()]
#' @param domain passed on to [stop()]
#'
#' @noRd
#'
#' @return TRUE on success
#'
#' @examples
#'
#' \dontrun{
#' assert(1 == 1)
#' assert(1 == 2)
#' }
#'
#'
assert <- function(
cond,
...,
call. = FALSE,
domain = NULL
){
if (identical(cond, TRUE)){
return(TRUE)
} else if (identical(cond, FALSE)){
if (identical(length(list(...)), 0L)){
msg <- paste0("`", deparse(match.call()[[2]]), "`", " is not 'TRUE'")
stop(msg, call. = call., domain = domain)
} else {
suppressWarnings( stop(..., call. = call., domain = domain) )
}
} else {
stop("Assertion must be either 'TRUE' or 'FALSE'")
}
}
assert_namespace <- function(...){
res <- vapply(c(...), requireNamespace, logical(1), quietly = TRUE)
if (all(res)){
return(invisible(TRUE))
} else {
pkgs <- c(...)
if (identical(length(pkgs), 1L)){
msg <- sprintf(paste(
"This function requires the package '%s'. You can install it with",
'`install.packages("%s")`.'), pkgs, pkgs
)
} else {
msg <- sprintf(
paste(
"This function requires the packages %s. You can install them with",
"`install.packages(%s)`."
),
paste(names(res)[!res], collapse = ", "),
deparse(names(res))
)
}
}
stop(msg)
}
# conditions --------------------------------------------------------------
#' Condition constructor
#'
#' A constructur function for conditions, taken from
#' \url{http://adv-r.had.co.nz/beyond-exception-handling.html}
#'
#' @param subclass Subclass to assign to the condition
#' @param message message to be passed to the condition
#' @param call call passed on to the conditon
#' @param ... further list elements to be passed on to the resulting object
#'
#' @return a condition object
#' @noRd
#'
#' @examples
#'
#' \dontrun{
#' # Construct a custom condition
#' malformed_log_entry_error <- function(text) {
#' msg <- paste0("Malformed log entry: ", text)
#' condition(
#' c("malformed_log_entry_entry", "error"),
#' message = msg,
#' text = text
#' )
#' }
#'
#'
#' # Signal the condition
#' parse_log_entry <- function(text) {
#' if (!well_formed_log_entry(text)) {
#' stop(malformed_log_entry_error(text))
#' }
#' }
#'
#'
#' # Handle the condition
#' tryCatch(
#' malformed_log_entry = function(e) NULL,
#' parse_log_entry(text)
#' )
#' }
#'
condition <- function(subclass, message, call = sys.call(-1), ...) {
structure(
class = c(subclass, "condition"),
list(message = message, call = call, ...)
)
}
error <- function(subclass, message, call = sys.call(-1), ...) {
structure(
class = c(subclass, "error", "condition"),
list(message = message, call = call, ...)
)
}
# predicates --------------------------------------------------------------
is_scalar <- function(x){
identical(length(x), 1L)
}
is_scalar_list <- function(x){
is_list(x) && is_scalar(x)
}
is_scalar_atomic <- function(x){
is.atomic(x) && is_scalar(x)
}
is_scalar_logical <- function(x){
is.logical(x) && is_scalar(x)
}
is_scalar_integer <- function(x){
is.integer(x) && is_scalar(x)
}
is_scalar_factor <- function(x){
is.factor(x) && is_scalar(x)
}
is_scalar_list <- function(x){
is.list(x) && is_scalar(x)
}
is_scalar_numeric <- function(x){
is.numeric(x) && is_scalar(x)
}
is_scalar_character <- function(x){
is.character(x) && is_scalar(x)
}
is_vector <- function(x){
is.atomic(x) || is.list(x)
}
is_bool <- function(x){
is.logical(x) && !anyNA(x)
}
#' Check if Object is a Boolean
#'
#' Check wheter an object is either `TRUE` or `FALSE`.
#'
#' @param x Any \R Object.
#' @return either `TRUE` or `FALSE`
#' @noRd
#'
is_scalar_bool <- function(x){
identical(x, TRUE) || identical(x, FALSE)
}
#' Check if Object is Integer-like
#'
#' Check wheter an object is either `TRUE` or `FALSE`.
#'
#' @param x Any \R Object.
#' @return either `TRUE` or `FALSE`
#' @noRd
#'
is_integerish <- function(x){
if (!is.numeric(x)){
FALSE
} else {
all(as.integer(x) == x)
}
}
is_scalar_integerish <- function(x){
is_scalar(x) && is_integerish(x)
}
is_n <- function(x){
is_scalar_integerish(x) && identical(x > 0, TRUE)
}
is_n0 <- function(x){
is_scalar_integerish(x) && identical(x >= 0, TRUE)
}
#' Check if Objects have the same length
#'
#' @param ... Any number of \R Objects.
#'
#' @return either `TRUE` or `FALSE`
#' @noRd
is_equal_length <- function(...){
lengths <- vapply(list(...), length, 1L)
identical(length(unique(lengths)), 1L)
}
#' Check if Object has length 0
#'
#' Check wheter an object is either `TRUE` or `FALSE`.
#'
#' @param x Any \R Object.
#' @return either `TRUE` or `FALSE`
#' @noRd
#'
is_empty <- function(x){
identical(length(x), 0L)
}
#' Check if a String is Blank
#'
#' Check wheter a character vector contains only of spaces
#'
#' @param x Any \R Object.
#' @return either `TRUE` or `FALSE`
#' @noRd
#'
is_blank <- function(x){
trimws(x) == ""
}
# all_are -----------------------------------------------------------------
#' Convert vector if identical elements to scalar
#'
#' Returns `unique(x)` if all elements of `x` are identical, throws an error if
#' not.
#'
#' @inheritParams all_are_identical
#'
#' @return A scalar of the same type as `x`
#' @noRd
as_scalar <- function(x){
res <- unique(x)
if (is_scalar(res)){
return(res)
} else {
stop("Not all elements of x are identical")
}
}
#' Test if all elements of a vector are identical
#'
#' @param x any object that can be handled by [unique()] (usually a vector or
#' list)
#' @param empty_value Value to return if function is called on a vector of
#' length 0 (e.g. `NULL`, `numeric()`, ...)
#'
#' @noRd
#' @family special equality checks
#' @return `TRUE/FALSE`
#'
#' @examples
#'
#' all_are_identical(c(1,2,3))
#' all_are_identical(c(1,1,1))
#'
all_are_identical <- function(x, empty_value = FALSE) {
assert(length(empty_value) <= 1)
if (length(x) > 0L) {
return(identical(length(unique(x)), 1L))
} else {
if (is.null(x)){
warning("'x' is NULL")
} else {
warning("'x' is an empty vector")
}
return(empty_value)
}
}
#' Test if all elements of a vector are unique
#'
#' @inheritParams all_are_identical
#'
#' @return TRUE/FALSE
#'
#' @noRd
#' @family special equality checks
#'
#' @examples
#'
#' all_are_identical(c(1,2,3))
#' all_are_identical(c(1,1,1))
#'
all_are_distinct <- function(
x,
empty_value = FALSE
){
assert(length(empty_value) <= 1)
if (identical(length(x), 1L)) {
return(TRUE)
} else if (length(x) > 1L) {
return(identical(length(unique(x)), length(x)))
} else {
if (is.null(x)){
warning("'x' is NULL")
} else {
warning("'x' is an empty vector")
}
return(empty_value)
}
}
n_distinct <- function(x){
length(unique(x))
}
# misc --------------------------------------------------------------------
pad_left <- function(
x,
width = max(nchar(paste(x))),
pad = " "
){
diff <- pmax(width - nchar(paste(x)), 0L)
padding <-
vapply(diff, function(i) paste(rep.int(pad, i), collapse = ""), character(1))
paste0(padding, x)
}
pad_right <- function(
x,
width = max(nchar(paste(x))),
pad = " "
){
diff <- pmax(width - nchar(paste(x)), 0L)
padding <-
vapply(diff, function(i) paste(rep.int(pad, i), collapse = ""), character(1))
paste0(x, padding)
}
`%||%` <- function(x, y){
if (is.null(x))
y
else (x)
}
preview_object <- function(
x,
width = 32,
brackets = c("(", ")"),
quotes = c("`", "`"),
dots = ".."
){
if (!is.atomic(x))
return(class_fmt(x))
if (is.numeric(x))
x <- format(x, justify = "none", drop0trailing = TRUE, trim = TRUE)
res <- ptrunc(x, collapse = ", ", width = width, dots = dots)
if (length(x) > 1)
res <- paste0(brackets[[1]], res, brackets[[2]])
else
res <- paste0(quotes[[1]], res, quotes[[2]])
res
}
# nocov end
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