Create a new enum class

Usage

new_enum(
  name,
  variants,
  package = topenv_package_name(parent.frame()),
  allow_na = TRUE,
  default = NULL
)

Arguments

name: String. Name of the new class.
variants: Character vector. Allowed values.
package: String or NULL. Package to attribute the class to. Defaults to the caller's package, if any.
allow_na: Bool. Whether NA_character_ is a valid value.
default: String or NULL. Default value used when the property is omitted. Must be one of variants, or NA if allow_na = TRUE. If NULL (the default), falls back to NA_character_ when allow_na = TRUE, otherwise the value stays required with no default.

Value

An S7 class generator that inherits from Enum.

Examples

GridShape <- new_enum("GridShape", c("Square", "Hexagon"))
#> Overwriting method convert(<character>, <GridShape>)
GridShape("Square")
#> <GridShape>
#>  @ value   : chr "Square"
#>  @ variants: chr [1:2] "Square" "Hexagon"
#>  @ allow_na: logi TRUE
GridShape(NA_character_)
#> <GridShape>
#>  @ value   : chr NA
#>  @ variants: chr [1:2] "Square" "Hexagon"
#>  @ allow_na: logi TRUE