Is a Variable in a Dataset a Date or Datetime Variable?

Checks if a variable in a dataset is a date or datetime variable

assert_date_var(
  dataset,
  var,
  dataset_name = rlang::caller_arg(dataset),
  var_name = rlang::caller_arg(var),
  message = NULL,
  class = "assert_date_var",
  call = parent.frame()
)

Arguments

dataset

The dataset where the variable is expected

Default value

none

var

The variable to check

Default value

none

dataset_name

The name of the dataset. If the argument is specified, the specified name is displayed in the error message.

Default value

rlang::caller_arg(dataset)

var_name

The name of the variable. If the argument is specified, the specified name is displayed in the error message.

Default value

rlang::caller_arg(var)

message

(string)
string passed to cli::cli_abort(message). When NULL, default messaging is used (see examples for default messages). "var_name" and "dataset_name", can be used in messaging.

Default value

NULL

class

Subclass of the condition.

call

The execution environment of a currently running function, e.g. call = caller_env(). The corresponding function call is retrieved and mentioned in error messages as the source of the error.

You only need to supply call when throwing a condition from a helper function which wouldn't be relevant to mention in the message.

Can also be NULL or a defused function call to respectively not display any call or hard-code a code to display.

For more information about error calls, see Including function calls in error messages.

Value

The function throws an error if var is not a date or datetime variable in dataset and returns the input invisibly otherwise.

Examples

library(lubridate)
#> 
#> Attaching package: ‘lubridate’
#> The following objects are masked from ‘package:base’:
#> 
#>     date, intersect, setdiff, union
library(dplyr)
library(rlang)

example_fun <- function(dataset, var) {
  var <- assert_symbol(enexpr(var))
  assert_date_var(dataset = dataset, var = !!var)
}

my_data <- tribble(
  ~USUBJID, ~ADT,
  "1",      ymd("2020-12-06"),
  "2",      ymd("")
)

example_fun(
  dataset = my_data,
  var = ADT
)

try(example_fun(
  dataset = my_data,
  var = USUBJID
))
#> Error in example_fun(dataset = my_data, var = USUBJID) : 
#>   Column "USUBJID" in dataset `dataset` must be a date or datetime, but is
#> a character vector.

example_fun2 <- function(dataset, var) {
  var <- assert_symbol(enexpr(var))
  assert_date_var(
    dataset = dataset,
    var = !!var,
    dataset_name = "your_data",
    var_name = "your_var"
  )
}

try(example_fun2(
  dataset = my_data,
  var = USUBJID
))
#> Error in example_fun2(dataset = my_data, var = USUBJID) : 
#>   Column "your_var" in dataset `your_data` must be a date or datetime, but
#> is a character vector.