From: "David A. Black" <dblack@...>
Date: 2008-08-28T02:09:42+09:00
Subject: Re: how to avoid passing by reference and how to copy objects

Hi --

On Wed, 27 Aug 2008, Adam Akhtar wrote:

> Hi after a bit of searching and reading im quite confused by this.
>
> I first learnt C so used to being able to pass by reference or by value.
> In Ruby its just by reference (so ive just found out after an hour of
> chasing a bug).

I know this sounds pedantic, but I think it's really pass by value,
with the values being references.

In other words, if you do this:

   a = [1,2,3]

you're binding the identifier a to a reference to the array. If you
then do:

   puts a

you're passing the value of a (which is a reference to an array) to
puts.

In practical terms it doesn't matter, but it helps make sense of, for
example, the fact that you can't pass a reference-by-reference.


David

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