setpen
;;; -*- logo -*-
to setpen :pen_data
ifelse equalp first bf :pen_data "reverse ~
[penreverse] ~
[ifelse equalp first bf :pen_data "erase ~
[penerase] ~
[penpaint]]
ifelse equalp first :pen_data "penup [penup] [pendown]
setpensize first bf bf :pen_data
setpencolor first bf bf bf :pen_data
setpenpattern first bf bf bf bf :pen_data
end
bury [setpen]