Close the Door

Methods for an R6 object can access its private fields by using the private$ prefix.

thing_factory <- R6Class(
  "Thing",
  private = list(
    a_field = "a value",
    another_field = 123
  ),
  public = list(
    do_something = function(x, y, z) {
      # Access the private fields
      paste(
        private$a_field, 
        private$another_field
      )
    }
  )
)

This exercise is part of the course

Object-Oriented Programming with S3 and R6 in R

View Course

Exercise instructions

A microwave oven factory has been partially defined for you. It has been updated to include a private door_is_open field, and a public open_door method.

Add a public method named close_door() to close the microwave door.
- The method should take no arguments.
- In the body of the function, set the door_is_open field to FALSE.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# Add a close_door() method
microwave_oven_factory <- R6Class(
  "MicrowaveOven",
  private = list(
    power_rating_watts = 800,
    door_is_open = FALSE
  ),
  public = list(
    cook = function(time_seconds) {
      Sys.sleep(time_seconds)
      print("Your food is cooked!")
    },
    open_door = function() {
      private$door_is_open <- TRUE
    },
    ___ = ___
    
    
  )
)

Edit and Run Code