From: Daniel Sheppard <daniels@...>
Date: 2005-10-25T09:24:48+09:00
Subject: Re: Reflection, observ(er|able) instance vars?

I generally use define_method only because it works better with the
syntax highlighting of SciTE, and also make the code look a little
unnatural... you also can't pass in real objects to be used by the
method, only things that are stringable.

class_eval %{
	def #{method_name}(*args)
		stuff
	end
}

gets all screwed up (the #{} string is treated as a comment), but 

define_method :method_name { |*args|
	stuff
}

works fine. If I was trying to make it run fast, I'd probably be using
class_eval, not define_method.

Evals can be slow, but you're only doing the eval once when it's a
class_eval, and then it's just like any other method, whereas with
define_method you're calling off to the proc object every time, which is
slower than a method call for each and every call.


> -----Original Message-----
> From: Trans [mailto:transfire@gmail.com] 
> Sent: Saturday, 22 October 2005 10:37 PM
> To: ruby-talk ML
> Subject: Re: Reflection, observ(er|able) instance vars?
> 
> 
> Hugh Sasse wrote:
> 
> > This "delivers us from eval" :-) but does define_method 
> offer anything 
> > else over the class_eval %{...} approach?  Maybe [only :-)] speed?
> 
> Daniel makes some fair points, but there's nothing wrong with 
> using class_eval here. In fact with eval it's more concise 
> the resulting code will be faster.
> 
> T.
> 
> 
> 
> 
#####################################################################################
This email has been scanned by MailMarshal, an email content filter.
#####################################################################################