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35 lines
866 B
Ruby
35 lines
866 B
Ruby
module ActiveSupport
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module Memoizable
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def self.included(base) #:nodoc:
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base.extend(ClassMethods)
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end
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module ClassMethods
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def memoize(symbol)
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original_method = "_unmemoized_#{symbol}"
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memoized_ivar = "@_memoized_#{symbol}"
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raise "Already memoized #{symbol}" if instance_methods.map(&:to_s).include?(original_method)
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alias_method original_method, symbol
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class_eval <<-EOS, __FILE__, __LINE__
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def #{symbol}
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if defined? #{memoized_ivar}
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#{memoized_ivar}
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else
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#{memoized_ivar} = #{original_method}
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end
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end
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EOS
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end
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end
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def freeze
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methods.each do |method|
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if m = method.to_s.match(/\A_unmemoized_(.*)/)
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send(m[1]).freeze
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end
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end
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super
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end
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end
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end
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