From: matt@... (matt neuburg)
Date: 2006-11-03T01:15:16+09:00
Subject: Re: variable pointer

Wilson Bilkovich <wilsonb@gmail.com> wrote:

>On Thu, 2 Nov 2006 dblack@wobblini.net wrote:
> >    a = person.address
> >    person.address = Address.find(some_other_address)
> >    puts a       # a has changed!

> I must be missing something. Isn't this how virtually all Ruby code works?

I had to do a double-take as well, so here's an example for the rest of
us newbies trying to follow the discussion.

Presume the following:

address = Struct.new(:street).new("Main")
address2 = Struct.new(:street).new("Oak")
person = Struct.new(:address).new(address)

Okay, now let's execute exactly the code being discussed:

[1]

a = person.address
person.address = address2
p a # Main

So assigning directly to person's address didn't change "a".

OTOH:

[2]

a = person.address
person.address.street = "Oak"
puts a.street # => Oak

So I think what's unexpected is that, in the RoR example, [1] behaves as
if it had been [2]. m.

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