match_value <- function(arg, choices, name = deparse(substitute(arg))) {
assert_scalar_character(arg)
if (!(arg %in% choices)) {
stop(sprintf("'%s' must be one of %s",
name, paste(squote(choices), collapse = ", ")))
}
arg
}
assert_is <- function(x, what, name = deparse(substitute(x))) {
if (!inherits(x, what)) {
stop(sprintf("'%s' must be a %s", name, paste(what, collapse = " / ")),
call. = FALSE)
}
invisible(x)
}
assert_scalar <- function(x, name = deparse(substitute(x))) {
if (length(x) != 1) {
stop(sprintf("'%s' must be a scalar", name), call. = FALSE)
}
}
assert_scalar_character <- function(x, name = deparse(substitute(x))) {
assert_scalar(x, name)
assert_character(x, name)
}
assert_character <- function(x, name = deparse(substitute(x))) {
if (!is.character(x)) {
stop(sprintf("'%s' must be a character", name), call. = FALSE)
}
}
assert_scalar_integer <- function(x, name = deparse(substitute(x))) {
assert_scalar(x, name)
assert_integer(x, name)
}
assert_integer <- function(x, name = deparse(substitute(x))) {
if (!(is.integer(x) || all(x - round(x) == 0))) {
stop(sprintf("'%s' must be an integer", name), call. = FALSE)
}
}
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