From: James Gray <james@...>
Date: 2008-01-09T04:27:27+09:00
Subject: Re: Ruby questions

On Jan 8, 2008, at 1:05 PM, Jeff M. wrote:

> Hello, peeps. I'm dipping my feet into Ruby waters (from Smalltalk).

Hello and welcome to Ruby.

> I see that Ruby 1.9 is out and Leopard shipped with 1.8.6. I also
> heard that 1.9 would introduce a new VM that would be significantly
> faster than 1.8. Is that the case?

It is faster in many cases, slightly slower in a few, and similar  
speed in some others.

> If so, is there a standard way of getting 1.9 on OS X or am I kinda  
> stuck waiting for Apple to "do their thing"?

The important thing to know is that Ruby 1.9 is currently a  
"development release."  It has known problems.  The core team is  
sorting those out, but it's going to take a little time to firm up.   
Thus, as a new user, I recommend you stick with 1.8.6 for now to avoid  
running into any of these issues.

To answer your question though:  you do not have to wait for Apple to  
upgrade Ruby for you, no.  Many of us keep our own build (in /usr/ 
local) and update it as we desire.

> However, if I ever wanted to distribute my code or
> a program, is there a proper way of distributing everything needed
> with it?

Short answer:  yes.

Longer answer:  how you handle this depends on how you distribute your  
software.  Gems can have dependencies, for example.  There are also  
some all-in-one-executable solutions.

> Perhaps I've missed this in documentation, but am I able to extend a
> class without subclassing? Something akin to "loose methods" in
> Smalltalk?

Sure.  Ruby has open classes, so we can add methods to them at any time:

   $ irb
   >> class String
   >>   def to_rot13
   >>     tr 'a-zA-Z', 'n-za-mN-ZA-M'
   >>   end
   >> end
   => nil
   >> "James Edward Gray II".to_rot13
   => "Wnzrf Rqjneq Tenl VV"

Hope that helps.

James Edward Gray II