From: Day <iamday@...>
Date: 2008-02-02T02:54:04+09:00
Subject: @var = change to accessor method? Why?

In ZenTest 3.9.0's release notes
(http://blog.zenspider.com/archives/2008/01/zentest_version_390_has_been_released.html),
it says, "Cleaned out nearly every @ and use accessor methods instead.
You should too."

My first thought was, "What?" So in a blog comment, I asked about it.
Here's that (brief) exchange:
http://blog.zenspider.com/archives/2008/01/zentest_version_390_has_been_released.html#comments.
I may still get an answer there, but it occurred to me that wider
discussion might be better anyway (and he's probably on this list,
yes?). I understand, now, that there is a difference and what that
difference is (I think), but I still don't see why the latter is
better.

So... what's the advantage of changing

class Thing
  attr_accessor :a

  def do_something(arg)
    @a = arg
  end
end

to...

class Thing
  attr_accessor :a

  def do_something(arg)
    self.a = arg
  end
end

Am I missing some context that's helpful in understanding this? I'd
think that it would be more valuable for readability to keep the @var
assignment since it clues you in to the nature of the variable (vs. a
class variable, etc.) than... anything else I can come up with. I will
be the first to admit that, "anything I can come up with," is a
pitifully small set of ideas. I'm not trying to say that this idea is
bad or whatever... I'm wondering what I don't know. Thanks in advance
for illumination.


Ben