From: David MacMahon <davidm@...>
Date: 2013-10-30T22:01:09-07:00
Subject: [ruby-core:58095] Re: [ruby-trunk - Feature #9064] Add support for	packages, like in Java


On Oct 30, 2013, at 9:26 PM, Nobuyoshi Nakada wrote:

> (13/10/31 5:15), David MacMahon wrote:
>> It would be nice if the following were allowed:
>> 
>> class Foo < Bar; end # class Foo extends Bar
>> class Foo; end       # class Foo still extends Bar
> 
> This is allowed already.

Wow!  Neat!  Thanks!  I had completely missed that!  I guess I should re-check my examples before complaining!!! :-)

>> class Foo; end       # class Foo has Object as a "stand-in" superclass
>> class Foo < Bar; end # class Foo replaces Bar as its "official" superclass
> 
> If it is allowed,
> 
>  class C; end
>  c = C.new
>  class C < String; end
>  c.size # will segfault
> 
> with the current object system.

Interesting.  Why would it segfault instead of at least raising NoMethodError?  It doesn't really matter now that I know the class can be reopened without specifying a superclass!  Changing the class hierarchy does seem a little dubious, but then again having open classes at all is probably considered dubious by some...

Thanks again,
Dave