From: Gregory Brown <gregory.t.brown@...>
Date: 2007-02-18T00:49:04+09:00
Subject: Re: Oppinions on RCR for dup on immutable classes

On 2/17/07, Stefan Rusterholz <apeiros@gmx.net> wrote:

> My issue is that I can't test that. I can only try and catch the
> exception. With dup that's not too terrible as it doesn't have
> side-effects. Still in my oppinion having to run code to see what
> happens is not a clean behaviour.

Oh, good point.

>> 1.respond_to?(:dup)
=> true

Then you need to rescue the exception.

If you *really* need this behaviour, you could just stick it in a file
somewhere and require it.

>> class Fixnum
>>   undef :dup
>> end
=> nil
>> 2.dup
NoMethodError: undefined method `dup' for 2:Fixnum


BTW, Matz, the only difference I suppose is that by having a
NoMethodError, we could make use of respond_to? as a check, but I
don't know if I think it's such a big deal that I'd be in support of a
RCR.