From: Robert Klemme <bob.news@...>
Date: 2004-12-15T00:12:19+09:00
Subject: Re: Mixin questions


"Johan Nilsson" <johan.nilsson@---.esrange.ssc.se> schrieb im Newsbeitrag
news:1103032112.3aa9129fd718fc17e4d9eb2e027a3e52@teranews...
>
> "Robert Klemme" <bob.news@gmx.net> wrote in message
> news:3286taF3it29pU1@individual.net...
> >
>
> [snip]
>
> >
> > You don't necessarily need a class method.  You can make it a method
in
> > Kernel, too:
> >
> > module Kernel
> > private
> >   def static_create(cl, stuff)
> >     o = cl.new
> >     o.my_stuff.duh! stuff
> >     o
> >   end
> > end
> >
> > f = static_create( Foo, "some stuff")
> >
> > Somehow I feel that a mixin might be a bit over the top - unless of
course
> > the mixin contains more code.
>
> Might be. Still I'd prefer:
>
> f = Foo.static_create("some stuff")
>
> I still don't see how the mixin can get to the protected methods
though - I
> get "NoMethodError: protected method 'my_stuff' called for ..." if I try
> somehing like my original code.

I haven't a solution for this yet.  I tried with instance_eval but to no
avail.  Maybe send works.  Did you try that?

> > > In english, I want to create an instance of Foo from within the
mixin's
> > > supplied class method. The first question still applies though.
> >
> > You mean like this?
> >
> > module Mix
> >   def test_it
> >     p self::FOO
> >   end
> > end
> >
> > class Test
> >   extend Mix
> >   FOO = "bar"
> > end
>
> Yes, but in my (unfortunately) more complex case I get "dynamic constant
> assignment" whenever I add "self::<constant>" to the mixin (reported
from
> the point where the class constant is defined).

But then you're assigning the constant more than once.  From your example
I though you just wanted to access (= read) it.  Which Ruby version are
you using?

> Using
> ...self.class.const_get("<constant>") works fine though in the mixin.

Strange.

> The code is a bit too much to post though, if I can reduce it I'll try
and
> post the actual failing code instead.

Yeah, it would be good to see the real source of the problem.  At the
moment I feel a bit tapping in the dark. :-)

Kind regards + good luck

    robert