From: Josh Cheek <josh.cheek@...>
Date: 2013-04-04T10:22:48+09:00
Subject: Re: Eigenclass: why this syntax?

--90e6ba10a96dcf461104d97eceb8
Content-Type: text/plain; charset=ISO-8859-1

On Wed, Apr 3, 2013 at 7:36 PM, Marc Heiler <lists@ruby-forum.com> wrote:

> - Also, in the above example, is it possible to query the @use_colours
> variable for when instance methods of module Foo are mixed into a class?
> I would like to mixin instance variables that are defined on the
> instance level of the module, inside methods defined in that module. So
> yeah, basically I want to use a module like a class, but it seems ruby
> gives obstacles to that attempt.
>
>
Not sure I understand the question, but it sounds like you want this:

module A
  attr_accessor :whatev
end

# include it in the singleton class
class B
  class << self
    include A
  end
  self.whatev = 'something'
  whatev # => "something"
end

# shorthand version of the above
class C
  extend A
  self.whatev = 'something'
  whatev # => "something"
end

--90e6ba10a96dcf461104d97eceb8
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

On Wed, Apr 3, 2013 at 7:36 PM, Marc Heiler <span dir=3D"ltr">&lt;<a href=
=3D"mailto:lists@ruby-forum.com" target=3D"_blank">lists@ruby-forum.com</a>=
&gt;</span> wrote:<br><div class=3D"gmail_quote"><blockquote class=3D"gmail=
_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:=
1ex">
- Also, in the above example, is it possible to query the @use_colours<br>
variable for when instance methods of module Foo are mixed into a class?<br=
>
I would like to mixin instance variables that are defined on the<br>
instance level of the module, inside methods defined in that module. So<br>
yeah, basically I want to use a module like a class, but it seems ruby<br>
gives obstacles to that attempt.<br>
<span class=3D"HOEnZb"><font color=3D"#888888"><br></font></span></blockquo=
te><div><br></div><div>Not sure I understand the question, but it sounds li=
ke you want this:</div><div><br></div><div><div>module A</div><div>=A0 attr=
_accessor :whatev</div>
<div>end</div><div><br></div><div># include it in the singleton class</div>=
<div>class B</div><div>=A0 class &lt;&lt; self</div><div>=A0 =A0 include A<=
/div><div>=A0 end</div><div>=A0 self.whatev =3D &#39;something&#39;</div><d=
iv>=A0 whatev # =3D&gt; &quot;something&quot;</div>
<div>end</div><div><br></div><div># shorthand version of the above</div><di=
v>class C</div><div>=A0 extend A</div><div>=A0 self.whatev =3D &#39;somethi=
ng&#39;</div><div>=A0 whatev # =3D&gt; &quot;something&quot;</div><div>end<=
/div></div>
<div><br></div></div>

--90e6ba10a96dcf461104d97eceb8--