R: Check if an argument is a vector of type character

checkCharacter {checkmate} | R Documentation

## Check if an argument is a vector of type character

### Description

Check if an argument is a vector of type character

### Usage

    checkCharacter(
      x,
      min.chars = NULL,
      pattern = NULL,
      fixed = NULL,
      ignore.case = FALSE,
      any.missing = TRUE,
      all.missing = TRUE,
      len = NULL,
      min.len = NULL,
      max.len = NULL,
      unique = FALSE,
      sorted = FALSE,
      names = NULL,
      null.ok = FALSE
    )

    check_character(
      x,
      min.chars = NULL,
      pattern = NULL,
      fixed = NULL,
      ignore.case = FALSE,
      any.missing = TRUE,
      all.missing = TRUE,
      len = NULL,
      min.len = NULL,
      max.len = NULL,
      unique = FALSE,
      sorted = FALSE,
      names = NULL,
      null.ok = FALSE
    )

    assertCharacter(
      x,
      min.chars = NULL,
      pattern = NULL,
      fixed = NULL,
      ignore.case = FALSE,
      any.missing = TRUE,
      all.missing = TRUE,
      len = NULL,
      min.len = NULL,
      max.len = NULL,
      unique = FALSE,
      sorted = FALSE,
      names = NULL,
      null.ok = FALSE,
      .var.name = vname(x),
      add = NULL
    )

    assert_character(
      x,
      min.chars = NULL,
      pattern = NULL,
      fixed = NULL,
      ignore.case = FALSE,
      any.missing = TRUE,
      all.missing = TRUE,
      len = NULL,
      min.len = NULL,
      max.len = NULL,
      unique = FALSE,
      sorted = FALSE,
      names = NULL,
      null.ok = FALSE,
      .var.name = vname(x),
      add = NULL
    )

    testCharacter(
      x,
      min.chars = NULL,
      pattern = NULL,
      fixed = NULL,
      ignore.case = FALSE,
      any.missing = TRUE,
      all.missing = TRUE,
      len = NULL,
      min.len = NULL,
      max.len = NULL,
      unique = FALSE,
      sorted = FALSE,
      names = NULL,
      null.ok = FALSE
    )

    test_character(
      x,
      min.chars = NULL,
      pattern = NULL,
      fixed = NULL,
      ignore.case = FALSE,
      any.missing = TRUE,
      all.missing = TRUE,
      len = NULL,
      min.len = NULL,
      max.len = NULL,
      unique = FALSE,
      sorted = FALSE,
      names = NULL,
      null.ok = FALSE
    )

    expect_character(
      x,
      min.chars = NULL,
      pattern = NULL,
      fixed = NULL,
      ignore.case = FALSE,
      any.missing = TRUE,
      all.missing = TRUE,
      len = NULL,
      min.len = NULL,
      max.len = NULL,
      unique = FALSE,
      sorted = FALSE,
      names = NULL,
      null.ok = FALSE,
      info = NULL,
      label = vname(x)
    )

### Arguments

`x` | [any] Object to check.
`min.chars` | [`integer(1)`] Minimum number of characters for each element of `x`.
`pattern` | [`character(1L)`] Regular expression as used in `grepl`. All non-missing elements of `x` must comply to this pattern.
`fixed` | [`character(1)`] Substring to detect in `x`. Will be used as `pattern` in `grepl` with option `fixed` set to `TRUE`. All non-missing elements of `x` must contain this substring.
`ignore.case` | [`logical(1)`] See `grepl`. Default is `FALSE`.
`any.missing` | [`logical(1)`] Are vectors with missing values allowed? Default is `TRUE`.
`all.missing` | [`logical(1)`] Are vectors with only missing values allowed? Default is `TRUE`.
`len` | [`integer(1)`] Exact expected length of `x`.
`min.len` | [`integer(1)`] Minimal length of `x`.
`max.len` | [`integer(1)`] Maximal length of `x`.
`unique` | [`logical(1)`] Must all values be unique? Default is `FALSE`.
`sorted` | [`logical(1)`] Elements must be sorted in ascending order. Missing values are ignored.
`names` | [`character(1)`] Check for names. See `checkNamed` for possible values. Default is “any” which performs no check at all. Note that you can use `checkSubset` to check for a specific set of names.
`null.ok` | [`logical(1)`] If set to `TRUE`, `x` may also be `NULL`. In this case only a type check of `x` is 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`.

### Details

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

### Value

Depending on the function prefix: If the check is successful, the functions `assertCharacter`/`assert_character` return `x` invisibly, whereas `checkCharacter`/`check_character` and `testCharacter`/`test_character` return `TRUE`. If the check is not successful, `assertCharacter`/`assert_character` throws an error message, `testCharacter`/`test_character` returns `FALSE`, and `checkCharacter` returns a string with the error message. The function `expect_character` always returns an `expectation`.

### See Also

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

### Examples

    testCharacter(letters, min.len = 1, any.missing = FALSE)
    testCharacter(letters, min.chars = 2)
    testCharacter("example", pattern = "xa")

[Package checkmate version 2.0.0 Index]