Check if an argument is a single atomic value
Usage
checkScalar(x, na.ok = FALSE, null.ok = FALSE)
check_scalar(x, na.ok = FALSE, null.ok = FALSE)
assertScalar(
  x,
  na.ok = FALSE,
  null.ok = FALSE,
  .var.name = vname(x),
  add = NULL
)
assert_scalar(
  x,
  na.ok = FALSE,
  null.ok = FALSE,
  .var.name = vname(x),
  add = NULL
)
testScalar(x, na.ok = FALSE, null.ok = FALSE)
test_scalar(x, na.ok = FALSE, null.ok = FALSE)
expect_scalar(x, na.ok = FALSE, null.ok = FALSE, info = NULL, label = vname(x))Arguments
- x
- [ - any]
 Object to check.
- na.ok
- [ - logical(1)]
 Are missing values allowed? Default is- FALSE.
- null.ok
- [ - logical(1)]
 If set to- TRUE,- xmay also be- NULL. In this case only a type check of- xis performed, all additional checks are disabled.
- .var.name
- [ - character(1)]
 Name of the checked object to print in assertions. Defaults to the heuristic implemented in- vname.
- add
- [ - AssertCollection]
 Collection to store assertion messages. See- AssertCollection.
- info
- [ - character(1)]
 Extra information to be included in the message for the testthat reporter. See- expect_that.
- label
- [ - character(1)]
 Name of the checked object to print in messages. Defaults to the heuristic implemented in- vname.
Value
Depending on the function prefix:
 If the check is successful, the functions
 assertScalar/assert_scalar return
 x invisibly, whereas
 checkScalar/check_scalar and
 testScalar/test_scalar return
 TRUE.
 If the check is not successful,
 assertScalar/assert_scalar
 throws an error message,
 testScalar/test_scalar
 returns FALSE,
 and checkScalar/check_scalar
 return a string with the error message.
 The function expect_scalar always returns an
 expectation.
Details
This function does not distinguish between
NA, NA_integer_, NA_real_, NA_complex_
NA_character_ and NaN.
See also
Other scalars:
checkCount(),
checkFlag(),
checkInt(),
checkNumber(),
checkScalarNA(),
checkString()