From: Mauricio Fernandez <mfp@...>
Date: 2006-08-07T07:13:04+09:00
Subject: Re: Superclass mismatches

On Mon, Aug 07, 2006 at 07:00:06AM +0900, listrecv@gmail.com wrote:
> I'm sometimes seeing an error "superclass mismatch".  I have no idea
> what this error is.  could anyone either explain it or point me to the
> docs (or src code)?

X = Class.new
Y = Class.new
class Foo < X; end
class Foo < Y; end
# ~> -:4: superclass mismatch for class Foo (TypeError)

In the above situation it's obvious that you're saying that Foo is derived
from X at first and then Y (!= X) the second time, but you might have run into
this problem with something like

class Foo < Struct.new(:a, :b, :c)
# ....
end

if you load()ed that file more than once (this can happen if you require()
the file under two different names), since each time Struct.new is evaluated
a new class will be created.

-- 
Mauricio Fernandez  -   http://eigenclass.org   -  singular Ruby