What's better about Ruby than Python?

[Alex Martelli]

Alexander Schmolck wrote:
   ...
> I recall the following, roughly in order of importance (treat with
> caution, it's some time that I looked at Ruby):
> 
> 0. I it's possible to redefine classes at runtime without going bonkers
>    (instances automatically get updated to the new class definitions).

This is generally feasible in Python, too -- but not with built-in types
(e.g., you can't redefine what "+" means on integers, while in Ruby you
could).

>    This, I think is by far python's greatest flaw, amongst other things it
>    greatly compromises its interactiveness, which is a key virtue. If
>    someone can explain to me how I'm wrong on this and python's behavior
>    really is sane, I'll be eternally grateful.

I don't think I understand what you're saying.  For example:

>>> class X:
...   def amethod(self): return 'just a method'
...
>>> x=X()
>>> x.amethod()
'just a method'
>>> def abettermethod(self): return 'ah, now THIS is better!'
...
>>> X.amethod = abettermethod
>>> x.amethod()
'ah, now THIS is better!'
>>>

Isn't this "redefining classes at runtime // instances automatically
get updated", too?  If you want to redefine a bunch of entries in X,
rather than just a few, X.__dict__.update(someotherdict) -- or even,
shudder, reassigning X.__dict__ altogether... -- may perhaps be 
preferable, but I personally like the explicitness of assignments
for most cases of such (rare) tasks.


Alex