Module: Pangea::Memoizers::SimpleMemoizer

Defined in:
lib/memoizers/simple_memoizer.rb

Overview

based on github.com/JackDanger/simple_memoize

Instance Method Summary collapse

Instance Method Details

#memoize(method_name, p = {}) ⇒ Object 



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# File 'lib/memoizers/simple_memoizer.rb', line 7

def memoize(method_name, p={})
  method_name = method_name.to_s
  stripped_method_name = method_name.sub(/([!?])$/, '')

  punctuation = $1
  wordy_punctuation = (punctuation == '!' ? '_bang' : '_huh') if punctuation
  ivar_name = "@#{stripped_method_name}#{wordy_punctuation}"

  memoized_method_name = "#{stripped_method_name}_with_timed_memo#{punctuation}"
  regular_method_name  = "#{stripped_method_name}_without_memo#{punctuation}"

  unless (instance_methods + private_instance_methods).include?(method_name)
    raise NoMethodError, "The Method '#{method_name}' cannot be memoized because it doesn't exist in #{self}"
  end
  return if self.method_defined?(memoized_method_name)
    
  self.class_eval "
    def #{memoized_method_name}(*args)
      if defined?(#{ivar_name})
        #{ivar_name}
      else
        #{ivar_name} = #{regular_method_name}(*args)
      end
    end
    alias_method :#{regular_method_name}, :#{method_name}
    alias_method :#{method_name}, :#{memoized_method_name}

    protected :#{method_name} if protected_instance_methods.include?('#{regular_method_name}')
    private   :#{method_name} if private_instance_methods.include?('#{regular_method_name}')
  "
end