[ruby-talk:21486] Chaining methods in Ruby (spinoff)

[Tobias Reif]
> intermingled01 = h.repeat.upcase.delete_digits
> puts intermingled01 # -> ABCABC
> 
> # doesn't work, because h.reverse returns a String

Ooops... seems I assumed too much about Ruby. Then it seems you have
no choice but to take the #method_missing approach outlined in the
other post.

On a general note though, shouldn't #upcase and #reverse return
objects of the same type in this situation? It is kind of surprising
that they don't. And to make subclassing easier, they should return
objects of type HoX.

That is, I would want the following

    Transformation operations, such as upcase, reverse, etc, should
    return an object of the same type as the original. (i.e. use
    self.class.new instead of String.new).

That would save a lot of delegation, in classes such as HoX and the
JavaArray class that was discussed in another thread. It would also
encourage people to put modified behavior in subclasses instead of
modifying the built-in classes directly, which could lead to name
collisions and other problems.

How far should this be taken? Should it also apply to binary methods
such as #+? How will performance be affected? Are there situations
when this approach would lead to complications/surprises?

Post your opinions and, if there is enough interest, I'll try to
gather them into an RCR.

// Niklas