vb: Validate input as boolean and replace with default on empty...

In langfob/bdpg: Package For Building and Testing Biodiversity Problem Generators

Validate input as boolean and replace with default on empty input if desired

Description

This function is intended to be a more flexible replacement for calling is.logical(). In particular, it makes it possible to replace empty values with a default value (e.g., FALSE) and to define whether NULL and/or NA are treated as empty values. It also allows control over whether numeric values are considered boolean by this validation function. This is sometimes useful when validating an input option where a numeric value would be suggestive of a mistake in the input file.

Usage

vb(
  var_value,
  def_on_empty = FALSE,
  def = FALSE,
  treat_NULL_as_empty = TRUE,
  treat_NA_as_empty = FALSE,
  allow_num = FALSE
)

Arguments

var_value	the value to be checked to see if it's a boolean
def_on_empty	boolean flag indicating whether to return a default value instead of the input value when the input value is empty (where empty is defined by other flags below)
def	a TRUE or FALSE default value to return instead of the input value when a default is requested
treat_NULL_as_empty	a boolean flag set to TRUE if a NULL input is to be treated as an empty input; FALSE otherwise
treat_NA_as_empty	a boolean flag set to TRUE if an NA input is to be treated as an empty input; FALSE otherwise
allow_num	a boolean flag set to TRUE if a numeric input is to be allowed and returned as FALSE if 0 and TRUE if non-zero

Details

Note that even if they are set to TRUE, the flags treat_NULL_as_empty and treat_NA_as_empty are ignored if def_on_empty is FALSE.

Value

Returns the input value if it is boolean or, returns a specified boolean if other arguments force a valid converted or default boolean to return; otherwise, throws an error

Examples

x <- TRUE
vb (x)
vb (-150, allow_num = TRUE)
vb (0, allow_num = TRUE)
vb (NULL, def_on_empty = TRUE)
vb (NULL, def_on_empty = TRUE, def = TRUE)
vb (NA, def_on_empty = TRUE, def = TRUE, treat_NA_as_empty = TRUE)
vb (NA, def_on_empty = TRUE, treat_NA_as_empty = TRUE)
vb (NULL, def_on_empty = TRUE, def = 10, treat_NULL_as_empty = TRUE, allow_num = TRUE)
## Not run: 
                #  These all generate errors
vb (1)                     #  error - not boolean & allow_num not set to TRUE
vb (0)
vb (1000)
vb ("aString")                        #  error - not boolean
vb (NULL)                             #  error - def_on_empty not set
vb (NA)            #  error - def_on_empty not set, treat_NA_as_empty not set
vb (NULL, treat_NULL_as_empty = TRUE) #  error - def_on_empty not set
vb (NA, treat_NA_as_empty = TRUE)     #  error - def_on_empty not set to TRUE
        #  error - non-numeric default, but allow_num not TRUE
vb (NA, def_on_empty = TRUE, def = 10, treat_NA_as_empty = TRUE)
         
## End(Not run)

langfob/bdpg documentation built on Dec. 8, 2022, 5:33 a.m.