enum: Create an enumerated type
| enum | R Documentation |
Create an enumerated type
Description
Creates an enumerated type with a fixed set of possible values. This function returns an enum generator, which can be used to create enum objects with values restricted to the specified set.
Usage
enum(...)
Arguments
... |
The possible values for the enumerated type. These should be unique character strings. |
Value
A function (enum generator) of class 'enum_generator' that creates enum objects of the defined type. The returned function takes a single argument and returns an object of class 'enum'.
See Also
interface for using enums in interfaces
Examples
# Create an enum type for colors
Colors <- enum("red", "green", "blue")
# Create enum objects
my_color <- Colors("red")
print(my_color) # Output: Enum: red
# Trying to create an enum with an invalid value will raise an error
try(Colors("yellow"))
# Enums can be used in interfaces
ColoredShape <- interface(
shape = character,
color = Colors
)
my_shape <- ColoredShape(shape = "circle", color = "red")
# Modifying enum values
my_shape$color$value <- "blue" # This is valid
try(my_shape$color$value <- "yellow") # This will raise an error
