checkmate (version 1.6.2)

checkString: Check if an argument is a string

Description

A string is defined as a scalar character vector.

Usage

checkString(x, na.ok = FALSE)
assertString(x, na.ok = FALSE, .var.name)
testString(x, na.ok = FALSE)
expect_string(x, na.ok = FALSE, info = NULL, label = NULL)

Arguments

x

[any] Object to check.

na.ok

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

.var.name

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

info

[character(1)] Extra information to be included in the message for the testthat reporter. See expect_that.

label

[character(1)] Same as .var.name, but passed down to expect_that.

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, checkString returns a string with the error message. The function expect_string will return an expectation.

Details

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

See Also

Other scalars: assertCount, checkCount, expect_count, testCount; assertFlag, checkFlag, expect_flag, testFlag; assertInt, checkInt, expect_int, testInt; assertNumber, checkNumber, expect_number, testNumber; assertPercentage, checkPercentage, expect_percentage, testPercentage; assertScalarNA, checkScalarNA, expect_scalar_na, testScalarNA; assertScalar, checkScalar, expect_scalar, testScalar

Examples

testString("a")
testString(letters)