From: Robert Dober <robert.dober@...>
Date: 2007-07-25T18:20:11+09:00
Subject: Re: Help: Get list of modules which are included in the class

On 7/25/07, FireAphis@gmail.com <FireAphis@gmail.com> wrote:
> 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.
What!!! Do I have to read the post in oder to answer now???

My bad you are right indeed.

> 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?
That is indeed more challenging :)
>
> FireAphis
>
>
>


-- 
I always knew that one day Smalltalk would replace Java.
I just didn't know it would be called Ruby
-- Kent Beck