stages follow the rules of dynamic scoping.. hmm..

gistfile1.txt

stage{'before':}->Stage['main']
include f
class f {
#  include b
  notify{'after':}
}
class b {
  notify{a:}
  notify{e:}

}
class a {
  include b
  notify{b:}
  notify{c:}
}
class { 'a':
  stage => before,
}