From: gabriele renzi <rff_rff@...>
Date: 2004-11-23T02:53:04+09:00
Subject: Re: Typical/idiomatic examples of dynamic code generation with Ruby?

Michael Neumann ha scritto:

>> In the paper I'm comparing "idiomatic" examples of how these languages
>> deal with common problems. Problem is, I'm quite new with Ruby and I'm
>> a bit at a loss for examples on how to show Ruby's strengths with
>> dynamic code generation (metaprogramming). That is often mentioned as 
>> one of Ruby's strengths. Don't get me wrong, I've found that Ruby has 
>> got the necesarry nuts and bolts but I couldn't really figure out what 
>> I could do with it, what I could not easily do with Python as well.
>>
>> So my question: do you know of any examples on the subject of dynamic
>> code generation which would be typical for Ruby and could not be
>> easily implemented in languages like Python?
> 

I'm not sure samples in ruby would be hard in python and viceversa, but 
there are different idioms. Maybe ruby has some more runtime hooks like 
Class#inherited or Module#included. I /think/ that a good example could 
be the Interface pkg (java style check for interfaces) 
http://raa.ruby-lang.org/project/interface/

Toghether with the just named  keyword-like class methods there is the 
class generation at runtime idiom, a built-in example is the Struct 
class, and a really nice one is Test::Unit::Mock, see a sample on this 
page: http://www.deveiate.org/code/Test-Unit-Mock/index.html

Another thing is the usual relying on method_missing tricks, for wich I 
guess the best example is the Criteria library (wich happen to generate 
sql instead of ruby, so not really metaprogramming I think :) look at:
http://mephle.org/Criteria/

It seem that your paper will be very interesting.. I even wonder how 
static languages handle this situations.

just my 0.02 euro