> Hi,
> 
> I implemented this one (patch attached), and came to conclusion that
> if someone really want this feature, it should be implemented in a
> subclass probably named "ChangeableTime" or "Time::Changeable".
> 
> Do you think we need a subclass?
> 
> For RCR#U011 detail, see http://www.rubygarden.com/ruby?NeedDiscussion
> 
>                                                         matz.
> 

My answer is yes. 

Why?

In terms of object-oriented analysis, a time-object will mostly be
considered as an attribute of a domain-object. Domain-objects (can)
have methods to change their internal state (also called setters).
Attributes (mostly) do not. To only way to change (the value of) an
attribute is to create a new object.

The fact of replacing the attribute with a new instance instead of
changing it's value is recommended in the lots of software engineering
practices. 

I would like to remark, I am viewing this from an software development
perspective. Probably there're some other perspectives that promote the
use of 'changeble'-methods for attributes. My opinion is influenced by
the fact I'm studying software engineering.
Also the text above about object-oriented analysis is very incomplete,
but I had no intention of posting a whole course.


Regards,
Paul.