Re: Fixnum#clone and Float#clone raise different exceptions

Yukihiro Matsumoto wrote:

> |4.clone -> 4 sounds better to me, but I must be missing something.
> 
> Do you accept the following behavior?
> 
>   a = 4
>   a.instance_eval{@a=5}
>   b = a.clone		# b = 4
>   b.instance_eval{@a=10}
>   a.instance_eval{@a}   # @a = 10
> 
> Similar thing can happen for a Float and singleton methods.

I think this is okay. I think getting an exception when doing obj.clone 
is a thing that would be against expected behavior more frequently than 
sharing instance variables on immediate Objects. (Instance variables on 
those are not used frequently anyway.)

I also think that the above change would bring back consistency between 
obj.clone and Marshal.load(Marshal.dump(obj)).

Maybe a note stating that you don't actually get a new object could be 
attached to the documentation of the clone and dup methods of Fixnum, 
Symbol, TrueClass, FalseClass and NilClass.