From: "FireAphis@..." <FireAphis@...>
Date: 2007-07-25T17:45:00+09:00
Subject: Re: Help: Get list of modules which are included in the class

On Jul 25, 11:21 am, "Robert Dober" <robert.do...@gmail.com> wrote:
> On 7/25/07, Chirag Mistry <chirag80b...@gmail.com> wrote:
>
> > Hi
>
> > I want to get a list of modules which are included directly in the class
> > in ruby. Example: Suppose below are two modules and a class defined in
> > ruby script.
> > -------------------
> > module M1
> >   ...
> > end
> > module M2
> >   ...
> > end
> > class MyClass
> >   include M1
> >   include M2
> >   ...
> > end
> > -------------------
> > How can I get list of modules which are included directly in the class?
> > Here in above example, M1 and M2 are only included in class MyClass so I
> > only want a list which contains modules M1 and M2 for MyClass. If we
> > call "MyClass.ancestors" which returns all the modules which are include
> > directly or indirectly in this class and all parent class hierarchy that
> > exactly I don't want to get.
>
> > Regards
> > Chirag
> > --
> > Posted viahttp://www.ruby-forum.com/.
>
> Maybe my friend irb can help ;)
> irb(main):001:0> module M1; end
> => nil
> irb(main):002:0> class C1; include M1 end
> => C1
> irb(main):003:0> module M2; end
> => nil
> irb(main):004:0> class C2 < C1; include M2 end
> => C2
> irb(main):017:0> class Module
> irb(main):018:1>   def included_modules
> irb(main):019:2>     ancestors.select{|x|x.class==Module}
> irb(main):020:2>   end
> irb(main):021:1> end
> irb(main):022:0>  C1.included_modules
> => [M1, Kernel]
> irb(main):023:0> C2.included_modules
> => [M2, M1, Kernel]
>
> You can get of Kernel of course if you do not want it to show up at the party.
> HTH
> Robert
>
> --
> I always knew that one day Smalltalk would replace Java.
> I just didn't know it would be called Ruby
> -- Kent Beck

I don't think that it answers the question. Look at the following
example:

irb(main):120:0> module M1
irb(main):121:1> end
=> nil
irb(main):122:0> module M2
irb(main):123:1> include M1
irb(main):124:1> end
=> M2
irb(main):125:0> class C1
irb(main):126:1> include M2
irb(main):127:1> end
=> C1
irb(main):128:0> C1.ancestors.select{|x|x.class==Module}
=> [M2, M1, Kernel]

I think that Chirag wanted to get only M2 and as you can see we get M1
as well. I personally think that there is no way to solve this. As far
as I know Ruby holds its ancestors internally in a plain list and
doesn't remember the hierarchy. Can someone tell more on this matter?

FireAphis