simmer_gate_test.R

library(R6)
library(simmer)

BatchGate <- R6Class("BatchGate",
                     public = list(
                       queue_length = 0,
                       opens_at_length = NA,
                       open = FALSE,
                       allowed_to_pass = 0,
                       initialize = function(opens_at_length){
                         self$opens_at_length = opens_at_length
                       },
                       join_queue = function(){
                         self$queue_length <- self$queue_length + 1
                       },
                       is_open = function(){
                         if(self$queue_length >= self$opens_at_length && self$open == FALSE){
                           self$open <- TRUE
                           self$allowed_to_pass <- self$opens_at_length
                         }
                         return(self$open)
                       },
                       pass_gate = function(){
                         self$queue_length <- self$queue_length - 1
                         self$allowed_to_pass <- self$allowed_to_pass - 1
                         
                         if(self$allowed_to_pass == 0) self$open <- FALSE
                       }
                       
                     ))

my_gate <- BatchGate$new(3)

env<-simmer()

t0 <- create_trajectory() %>%
  timeout(function() { # dummy to join queue
    my_gate$join_queue()
    0
    }) %>%
  timeout(.001) %>% # dummy to simulate wait in queue, dislike that we need to enter a number heer
  rollback(1, check=function(){
    if(my_gate$is_open()){
      # pass the gate
      my_gate$pass_gate()
      return(FALSE) # i.e. don't roll back
    } else return(TRUE)
  }) %>%
  timeout(function(){
    print("Passed the gate! Let's roll!")
    0
  })

env <- env %>%
  add_generator("ships", t0, at(0, 5, 10, 10, 15, 20)) %>%
  run()

get_mon_arrivals(env)