25 lines
556 B
Ruby
25 lines
556 B
Ruby
# The singleton pattern is used to ensure that there is only one instance of a
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# class and provides global access to that instance. This pattern is useful when
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# you want one instance of a class and many different objects need to access it,
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# rather than pass the object around, we can make the object global.
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class Singleton
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def self.new
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@instance ||= super
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end
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end
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# Other example
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require 'singleton'
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class OtherSingleton
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include Singleton
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# OtherSingleton.new is not allowed
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end
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# Usage
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s1 = Singleton.new
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s2 = OtherSingleton.instance
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