[ruby-core:18297] Re: Am I right that this is wrong?

Hi --

On Thu, 14 Aug 2008, Yukihiro Matsumoto wrote:

> Hi,
>
> In message "Re: [ruby-core:18275] Re: Am I right that this is wrong?"
>    on Thu, 14 Aug 2008 04:04:12 +0900, "David A. Black" <[e-mail]> writes:
>
> |There was a discussion about this at the Ruby Hoedown. As Jim Weirich
> |pointed out, the nice thing about doing it the other way around is
> |that you could do:
> |
> |   MyClass.instance_methods(:ancestors => true)
> |
> |or
> |
> |   MyClass.instance_methods(:with_ancestors)
> |
> |or whatever, whereas to make the argument false, you have to use false
> |or nil which is very cryptic.
>
> Interesting.  But in a dynamic language like Ruby, inheritance is just
> a mean to share methods and other attributes among classes, so that
> it's not as important as in static typed languages e.g. Java.  When we
> want to know the instance methods of a class, we have more focus on
> the list of methods effective in the instances of the class, not the
> list of methods defined (but not inherited) in particular class.
> Considering the less importance of inheritance in Ruby, I think the
> default should be as it is implemented now.

I understand, but I'll add that in practice, I find myself using
(false) more often than not. When I'm asking classes about their
instance methods, it's usually to find out something like which
methods they've overridden:

   Array.instance_methods(false) & Enumerable.instance_methods(false)

and things like that. Most of the time, the question "What can an
instance do?" seems to be handled at the instance level, with #methods
or #respond_to?

> If you want to have separate method to get the no-ancestors list of
> methods, it's OK as long as we get the "right" name for it.

How about "instance_methods!" :-)


David

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