An alternative to stopifnot/assert_that etc

This function makes it easy to use the {purrr} functions every(), some() and none() to handle vector inputs of length >= 1, and supports the seamless use of glue strings in the custom error message. Not suitable for checking if length(x) == 1 as it will check vectors element-wise, so will potentially return TRUE even if length(x) > 1

Usage

check_vec(
  x,
  predicate,
  message,
  which = c("every", "some", "none"),
  pf = parent.frame()
)

Arguments

x

The object to be checked

predicate

The predicate function used to check elements of x

message

A custom error message, as a string. Will be shown to the user if the predicate check does not succeed. Can include glued variables and {cli} semantic markup. Variable values will be searched for in the environment of the caller function (not in the environment of check_vec() ). This makes it easier to include informative values in the message.

which

One of "every", "some", "none", as a string. Defines which {purrr} function to use when applying the predicate. "every", the default, means that check_vec() will succeed if every value of x satisfies the predicate. "none" can be used to generate an inverse predicate, or the situation where success means that none of the elements of x satisfies the predicate. "some" is unlikely to be useful often, but it is available.

pf

Set as parent.frame() so variables in the caller environment can be used in the custom error message.

See also

check_scalar_type()