Mega Code Archive
As an interface
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class Duck
def quack
'Quack!'
end
def swim
'Paddle paddle paddle...'
end
end
class Goose
def honk
'Honk!'
end
def swim
'Splash splash splash...'
end
end
class DuckRecording
def quack
play
end
def play
'Quack!'
end
end
def make_it_quack(duck)
duck.quack
end
make_it_quack(Duck.new) # => "Quack!"
make_it_quack(DuckRecording.new)
# TypeException: object not of type Duck
]]>