зеркало из https://github.com/github/ruby.git
47 строки
1010 B
Ruby
47 строки
1010 B
Ruby
# Observable Mixin
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#
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# Observers must respond to update
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module Observable
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def add_observer(observer)
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@observer_peers = [] unless defined? @observer_peers
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unless observer.respond_to? :update
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raise NameError, "observer needs to respond to `update'"
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end
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@observer_peers.push observer
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end
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def delete_observer(observer)
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@observer_peers.delete observer if defined? @observer_peers
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end
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def delete_observers
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@observer_peers.clear if defined? @observer_peers
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end
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def count_observers
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if defined? @observer_peers
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@observer_peers.size
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else
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0
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end
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end
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def changed(state=true)
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@observer_state = state
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end
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def changed?
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if defined? @observer_state and @observer_state
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true
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else
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false
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end
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end
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def notify_observers(*arg)
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if defined? @observer_state and @observer_state
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if defined? @observer_peers
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for i in @observer_peers.dup
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i.update(*arg)
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end
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end
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@observer_state = false
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end
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end
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end
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