# a Person type declared in sig/person.rbs class Person @name: String @contacts: Array[Email] def initialize: (name: String) -> untyped def name: -> String def contacts: -> Array[Email] end # an Email type declared in sig/email.rbs (and referenced on lines 4 and 8 above) class Email @address: String def initialize: (address: String) -> untyped def address: -> String end