From: "David A. Black" <dblack@...>
Date: 2009-06-26T04:59:31+09:00
Subject: Re: Attr Methods and object setters

Hi --

On Fri, 26 Jun 2009, Marc Heiler wrote:

>> no, we don't. I'd argue strongly against "so many". It is highly non-
>> idiomatic.
>
> Ruby/GTK
>
> I guess I can hunt around which ruby-projects are using set_*
> specifically just to document whether it is common or not, but I can
> already see that my question is not addressed regarding the attr*
> decisions.

Do you mean something like

   attr_accessor_using_set_and_get_methods :name

I'm not sure how to analyze why this isn't in the language, since I
can't picture it being there. I guess it's partly because the language
supports the idea of attributes as pseudo-L-values; in other words,
when you do this:

   person.name = "David"

you're doing something that looks like an assignment, but is actually
a method call. Lots of things in Ruby look like something but are
actually method calls (like array[1] = 100, or the when clauses in a
case statement).

Also, set_name(arg) is really just another method. There's nothing
special about it. Someone might decide to avoid writing accessor
methods and write get/set ones instead (though I discourage it), but
they might decide to write lots of different methods, and the language
can't provide shortcuts for all of them.


David

-- 
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