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checkmate (version 1.7.2)

checkFunction: Check if an argument is a function

Description

Check if an argument is a function

Usage

checkFunction(x, args = NULL, ordered = FALSE, nargs = NULL)
assertFunction(x, args = NULL, ordered = FALSE, nargs = NULL,
  add = NULL, .var.name)
assert_function(x, args = NULL, ordered = FALSE, nargs = NULL,
  add = NULL, .var.name)
testFunction(x, args = NULL, ordered = FALSE, nargs = NULL)
test_function(x, args = NULL, ordered = FALSE, nargs = NULL)
expect_function(x, args = NULL, ordered = FALSE, nargs = NULL,
  info = NULL, label = NULL)

Arguments

x
[any] Object to check.
args
[character] Expected formal arguments. Checks that a function has no arguments if set to character(0). Default is NULL (no check).
ordered
[logical(1)] Flag whether the arguments provided in args must be the first length(args) arguments of the function in the specified order. Default is FALSE.
nargs
[integer(1)] Required number of arguments, without .... Default is NULL (no check).
add
[AssertCollection] Collection to store assertions. See AssertCollection.
.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, the functions return TRUE. If the check is not successful, assertFunction/assert_function throws an error message, testFunction/test_function returns FALSE, and checkFunction returns a string with the error message. The function expect_function always returns an expectation.

See Also

Other basetypes: checkArray, checkAtomicVector, checkAtomic, checkCharacter, checkComplex, checkDataFrame, checkDataTable, checkEnvironment, checkFactor, checkIntegerish, checkInteger, checkList, checkLogical, checkMatrix, checkNumeric, checkVector

Examples

Run this code
testFunction(mean)
testFunction(mean, args = "x")

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