checkmate (version 1.0)

checkString: Check if an argument is a string

Description

A string a scalar character vector.

Usage

checkString(x, na.ok = FALSE)
assertString(x, na.ok = FALSE, .var.name)
testString(x, na.ok = FALSE)

Arguments

x

[ANY] Object to check.

.var.name

[character(1)] Name for x. Defaults to a heuristic to determine the name using deparse and substitute.

na.ok

[logical(1)] Are missing values allowed? Default is FALSE.

Value

• Depending on the function prefix: If the check is successful, all functions return TRUE. If the check is not successful, assertString throws an error message, testString returns FALSE and checkString returns a string with the error message.

Details

This function does not distinguish between NA, NA_integer_, NA_real_, NA_complex_ NA_character_ and NaN.

See Also

Other scalars: assertCount, checkCount, testCount; assertFlag, checkFlag, testFlag; assertInt, checkInt, testInt; assertNumber, checkNumber, testNumber; assertScalarNA, checkScalarNA, testScalarNA; assertScalar, checkScalar, testScalar

Examples

testString("a")
 testString(letters)