From: Robert Dober <robert.dober@...>
Date: 2007-06-17T03:36:35+09:00
Subject: Re: Error in ancestor?

On 6/16/07, Morton Goldberg <m_goldberg@ameritech.net> wrote:
> On Jun 16, 2007, at 9:56 AM, Robert Dober wrote:
>
> > Hi list
> >
> > I just observed this (and it cost me quite some effort to debug my
> > code :( )
> >
> > 515/15 > ruby -ve 'class << Class::new; puts self; puts
> > ancestors.inspect end'
> > ruby 1.8.5 (2006-12-04 patchlevel 2) [i686-linux]
> > #<Class:#<Class:0xb7dfae50>>
> > [Class, Module, Object, Kernel]
> >
> >
> > this seems to be in contradiction with
> > http://www.ruby-doc.org/core/classes/Module.html#M001700
> > stating
> > ----------------------------------------------------------------------
> > -------
> >  mod.ancestors → array
> >
> > Returns a list of modules included in mod (including mod itself).
> >
> > =============
> >
> >   module Mod
> >     include Math
> >     include Comparable
> >   end
> >
> >   Mod.ancestors    #=> [Mod, Comparable, Math]
> >   Math.ancestors   #=> [Math]
> > ----------------------------------------------------------------------
> > -----
> >
> > Is this an error in doc or in behavior?
>
> It cost me some effort to figure out what the question really
> was :),  but I presume you're wondering why the singleton class

I know in ruby I would say
assert didactic_skills.zero? # :(

> doesn't appear in the ancestor list. I don't know the answer, but I
> think the question is posed more clearly when the example is
> constructed for the singleton class of an ordinary object.
>
> <code>
> class Foo; end
> Bar = class << Foo.new; self; end
> Bar # => #<Class:#<Foo:0x20e18>>
> Bar.ancestors # => [Foo, Object, Kernel]
> </code>

Sure thanks for adding this
>
> If I had to make a call, I would say that the documentation had
> inadvertently omitted a very special case.
Very probable given the code in class.c
>
> Regards, Morton
>
> P.S. Why 'puts ancestors.inspect' instead of the simpler 'p ancestors'?

Because output is shorter and more readable. I often get bitten by
debugging output
puts ary1
puts ary2
### Where the heck does ary2 start?

so I developed a reflex to use inspect for all kind of
debugging/demonstrating output.
I feel it is goo[df] practice.

Cheers
Robert
>
>


-- 
You see things; and you say Why?
But I dream things that never were; and I say Why not?
-- George Bernard Shaw