external-generic.md
In S7: An Object Oriented System Meant to Become a Successor to S3 and S4

displays nicely

Code
  print(bar)
Output
  <S7_external_generic> foo::bar(x)

new_method works with both hard and soft dependencies

Code
  args(Foo)
Output
  function (bar = t0::`An S7 Class`()) 
  NULL
Code
  args(t2::`An S7 Class 2`)
Output
  function (bar = t0::`An S7 Class`()) 
  NULL
Code
  args(t2:::`An Internal Class`)
Output
  function (foo = t0::`An S7 Class`(), bar = `An S7 Class 2`()) 
  NULL

Code
  new_class("Foo", properties = list(bar = new_class("Made Up Class", package = "t0")))
Condition
  Error:
  ! 'Made Up Class' is not an exported object from 'namespace:t0'
Code
  new_class("Foo", properties = list(bar = new_class("Made Up Class", package = "Made Up Package")))
Condition
  Error in `loadNamespace()`:
  ! there is no package called 'Made Up Package'
Code
  modified_class <- t0::`An S7 Class`
  attr(modified_class, "xyz") <- "abc"
  new_class("Foo", properties = list(bar = modified_class))
Condition
  Error:
  ! `t0::An S7 Class` is not identical to the class with the same @package and @name properties