R/rc_objects.R

In rryesuafuga/myfridge: What the package does (short line)

#' @import methods
#' @exportClass fridge

# The function is called "create_fridge" and the object is called "fridge"
  create_fridge <-  setRefClass("fridge",
              

              fields = list(fridge_content = "data.frame", 
                            fridge_volume = "numeric",
                            volume_taken = "numeric",
                            free_space = "numeric",
                            added_fridge_content = "data.frame"),
              
              methods = list(
                
                initialize = function(fridge_content, fridge_volume){
                  
                  stopifnot(is.data.frame(fridge_content))
                  stopifnot(ncol(fridge_content)==3) 
                  
                  fridge_content <<-
                    setNames(data.frame(matrix(ncol = 3, nrow = 0)), 
                             c("product_id", "amount", "unit_space"))
                  
                  
                  # more calculations needed here
                  volume_taken <<- as.numeric(fridge_content$amount %*% 
                                   fridge_content$unit_space)
                  
                  free_space <<- fridge_volume - volume_taken
                  
                  # initialisations
                  .self$fridge_content <- fridge_content
                  .self$fridge_volume <- fridge_volume
                  .self$volume_taken <- volume_taken
                  .self$free_space <- free_space
                  .self$added_fridge_content <- added_fridge_content
                  .self
    
                }
                
                ,
                
                
                # more methods follow here
                
                add_to_fridge = function(.self, added_fridge_content) {
                
                   stopifnot(is.data.frame(added_fridge_content))
                   stopifnot(ncol(added_fridge_content)==3)
                
                   added_fridge_content <<-
                     setNames(data.frame(matrix(ncol = 3, nrow = 0)),
                              c("product_id", "amount", "unit_space"))

                   if(added_fridge_content$product_id %in%
                      .self$fridge_content$product_id){
                  
                     .self$fridge_content$amount[ which(added_fridge_content$product_id %in%
                     .self$fridge_content$product_id)] <<-
                     added_fridge_content$amount +
                     .self$fridge_content$amount[ which(added_fridge_content$product_id %in%
                     .self$fridge_content$product_id)]
                  
                   } else(!(added_fridge_content$product_id %in%
                             .self$fridge_content$product_id))
                       .self$fridge_content <<-
                      rbind(.self$fridge_content, added_fridge_content)

                  }
                  
                  
                  
                  
      
              )
              
              
              
)