Comments on: About Metaprogramming speed

By: Emmanuel Oga

Emmanuel Oga — Wed, 18 Jun 2008 07:03:00 +0000

The main speed gain comes from changing define_method with one of the class_eval/eval forms.
Be careful, you have an error in one of the implementations:



module RefaMetaTimeDSL

  …

  def r_#{meth}

    #{amount.is_a?(Array) ? "#{amount[0]}.#{amount[1]}" : "#{amount}"}

  end

end
#The correct form should have been:

    #{amount.is_a?(Array) ? "#{amount[0]}.#{amount[1]}" : "#{amount} * self"}

By: Emmanuel Oga

Emmanuel Oga — Wed, 18 Jun 2008 07:03:00 +0000

Sorry, I don’t know if my last comment has been received. You have an error on: RefaMetaTimeDSL



 #{amount.is_a?(Array) ? "#{amount[0]}.#{amount[1]}" : "#{amount}"}

should be:



 #{amount.is_a?(Array) ? "#{amount[0]}.#{amount[1]}" : "#{amount} * self"}

So the main speed difference is in using class_eval instead of define_method.

By: ruby licious

ruby licious — Wed, 18 Jun 2008 07:03:00 +0000

Very nice article, I’ve often wondered about this but never got around to actually benchmark it.

By: Eike Herzbach

Eike Herzbach — Wed, 18 Jun 2008 07:03:00 +0000

Some of your examples have 364.25 days per year, which is wrong.