create sensible $print functions for the different R6 classes

[Bart6114]

low priority

consider:

> simmer()
<Simmer>
  Public:
    add_generator: function
    add_resource: function
    clone: function
    get_capacity: function
    get_generators: function
    get_mon_arrivals: function
    get_mon_attributes: function
    get_mon_resources: function
    get_n_generated: function
    get_queue_count: function
    get_queue_size: function
    get_resources: function
    get_server_count: function
    initialize: function
    name: anonymous
    now: function
    peek: function
    reset: function
    run: function
    step: function

  Private:
    mon_gen: NULL
    mon_res: NULL
    sim_obj: externalptr

a minimal example:

Simmer <- R6Class("Simmer",
  public = list(
    print = function() cat(paste0(
      "Simmer instance: ",self$name,"\n",
      "============================\n",
      "current sim time: ", self$now())),
    ....etc.....

which results in:

> simmer()
Simmer instance: anonymous
============================
current sim time: 0

[Enchufa2]

Some work on this: 9ee806e. I don't know if you had in mind something... nicer. 😄 I didn't feel very... creative, so I confined myself to the trajectory output format.

Note: now Trajectory$print() points to Trajectory$show(), and therefore create_trajectory() and create_trajectory() %>% show_trajectory() do the same.

[Bart6114]

It's already a lot better than the raw R6 show function 😄

What about deprecating the show_trajectory function? As simply printing the object returns the same output, I don't really see use for the show_trajectory func.

[Enchufa2]

+1. How do we do that? Simply by specifying in the docs "(deprecated)"? Additionally showing a warning?

[Enchufa2]

Oh, I see how it's done.