Module: Singleton

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# File 'opal/stdlib/singleton.rb', line 22
def __init__(klass)
 klass.instance_eval do
 @singleton__instance__ = nil
 end
 def klass.instance
 return @singleton__instance__ if @singleton__instance__
 @singleton__instance__ = new
 end
 klass
end

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# File 'opal/stdlib/singleton.rb', line 33
def included(klass)
 super
 klass.extend SingletonClassMethods 
 Singleton .__init__ (klass)
end

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# File 'opal/stdlib/singleton.rb', line 2
def clone
 raise TypeError, "can't clone instance of singleton #{self.class}"
end

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# File 'opal/stdlib/singleton.rb', line 6
def dup
 raise TypeError, "can't dup instance of singleton #{self.class}"
end