From: Robert Klemme <shortcutter@...>
Date: 2009-08-13T05:55:09+09:00
Subject: Re: Class#descendants?

On 12.08.2009 21:57, Jason Lillywhite wrote:
> Robert Klemme wrote:
> 
>> ObjectSpace.each_object(Class) do |cl|
>>    cl.superclass.ancestors.each {|scl| h[scl] << cl}
>> end
> 
> I'm getting this error:
> 
> irb(main):085:0> ObjectSpace.each_object(Class) do |cl|
> irb(main):086:1*    cl.superclass.ancestors.each {|scl| h[scl] << cl}
> irb(main):087:1> end
> NoMethodError: undefined method `ancestors' for nil:NilClass
>         from (irb):86
>         from (irb):85:in `each_object'
>         from (irb):85
>         from :0
> 
> Is there a reason superclass is returning nil on cl?

Oops, I inserted "superclass" after doing the test.  This is likely the 
case of Object.  If you remove it it works as well.  Sorry, for the hassle.

Kind regards

	robert

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