From: Brian Candler <b.candler@...>
Date: 2011-10-05T18:00:29+09:00
Subject: Re: Local vs method vs instance

Darryl Pierce wrote in post #1025016:
> On 10/04/2011 11:42 AM, Chris Hulan wrote:
>> but doing it this way makes the x public readable, so should only be
>> used if that is needed
>> I'd stick with using @x
>
> AH! That's what I missing, and what he meant by "the method". Okay. The
> OP though didn't have the attr_accessor on the fields, though, that I
> remember.

This was implied by the use of 'other.x'. If you can write 'other.x' 
then that object must have a method called 'x'. Since we're talking 
about adding two objects of the same class, this means self also has a 
method 'x', and you can call this just using 'x'.

Now, if you don't want to have accessors on your Point class, then it 
gets a little bit messy to tinker with the internals of the other 
object: e.g.

  @x + other.instance_variable_get(:@x)

or

  @x + other.instance_eval { @x }

I think you could also use a 'protected' accessor method, but I've never 
found the need to use those.

-- 
Posted via http://www.ruby-forum.com/.