From: Pit Capitain <pit@...>
Date: 2007-03-14T18:42:56+09:00
Subject: Re: Where is my Class ?

sur max schrieb:
> (...)
> B=a  # warning: already initialized constant B
> (...)
> this means that the Class B is overwritten by the Class referenced by "a"
> so it is the case of changing a constant. Is that possible ?

No, no objects are overwritten in Ruby. An assignment like

   var = obj

just makes the object on the right (obj) accessible via the name on the 
left (var). The line

   B = a

makes the object referenced by a (the anonymous class) accessible via 
the name B. After this, a and B are different names for the same object. 
The previous object referenced by the name B is still around (until the 
garbage collector reclaims it) and not changed at all.

In Ruby, constants, instance, and local variables are only names for 
objects. Constants have the additional property that they are intended 
to be assigned to only once. If you re-assign a constant, you get a 
warning, but the assignment happens nonetheless. Try this with something 
different than anonymous classes and it might be easier to understand.

There have been many discussions about variable names and objects on 
this mailing list. You can also look at

   http://onestepback.org/index.cgi/Tech/Ruby/Shoeboxes.rdoc

Regards,
Pit