checkmate (version 1.9.3)

checkNull: Check if an argument is NULL

Description

Check if an argument is NULL

Usage

checkNull(x)
check_null(x)
assertNull(x, .var.name = vname(x), add = NULL)
assert_null(x, .var.name = vname(x), add = NULL)
testNull(x)
test_null(x)

Arguments

x

[any] Object to check.

.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.

Value

Depending on the function prefix: If the check is successful, the functions assertNull/assert_null return x invisibly, whereas checkNull/check_null and testNull/test_null return TRUE. If the check is not successful, assertNull/assert_null throws an error message, testNull/test_null returns FALSE, and checkNull returns a string with the error message. The function expect_null always returns an expectation.

See Also

Other basetypes: checkArray, checkAtomicVector, checkAtomic, checkCharacter, checkComplex, checkDataFrame, checkDate, checkDouble, checkEnvironment, checkFactor, checkFormula, checkFunction, checkIntegerish, checkInteger, checkList, checkLogical, checkMatrix, checkNumeric, checkPOSIXct, checkRaw, checkVector

Examples

# NOT RUN {
testNull(NULL)
testNull(1)
# }