From: Trans <transfire@...>
Date: 2005-09-23T03:36:39+09:00
Subject: Re: Instantiating a subclass of NilClass.


Logan Capaldo wrote:
> On Sep 22, 2005, at 1:01 PM, Trans wrote:
>
> >> Why do you need the boolean behavior?
> >>
> >
> > In particular, I use the boolean behavior to redefine an element of
> > the
> > OpenStruct-like object under certain circumstances.
> >
> >   unless o.m  # could be null
> >     o.m = foo
> >
> > Right now I'm using 'if o.m.nil?' but it's not nice. It means one must
> > be aware of ths possibiliy of a null rather than nil. And what if
> > false
> > plays a role? I don't want the end user to have to worry about it. It
> > should be just like nil except not error when method missing.
> >
> > T.
> >
> >
> >
>
> Whats the problem with just doing
>
> def nil.method_missing(*args)
>         self
> end
>
> I think this might be an issue of having your cake and eating it too.

I eat lots of cake ;)

That can be done, but WATCH OUT! Other programs might depend on the
current behavior. And at the very least we frequently depend on nil
choking on #[] and other methods to tell us we have a bug in out
program. So I think its too risky. But correct me if I've over stated
the issue.

Thanks,
T.