From: HaPK <theHaPK@...>
Date: 2005-09-21T20:59:20+09:00
Subject: Re: Problem with constants

HaPK wrote:

> Kroeger Simon (ext) wrote:
>
>> I'm puzzled:
>> -----------------------
>> class X
>>  A = 1
>>  def X.a
>>    A
>>  end
>> end
>>
>> class Y < X
>>  A = 2
>> end
>>
>> class Z < X
>>  A = 3
>>  def Z.a
>>    A
>>  end
>> end
>>
>> p X.a #=> 1
>> p Y.a #=> 1
>> p Z.a #=> 3
>> -----------------------
>> (ruby 1.8.2 (2004-12-25) [i386-mswin32])
>>
>> Shouldn't this yield at least a warning?
>> Is this a feature?
>>  
>>
> Since A is not a class variable (it's a local variable) it's saved in 
> "X.a" closure. In Y class it doesn't exist, so it can't influence on 
> "X.a" method.
>
> PS I hope my crappy english doesn't mess things too much.

Ooops... sorry.. Didn't get you right.

Indeed, seems like a bug with constants assignment.

class X
  A = 1
end

class Y < X
  A = 2
end

class Z < X
end

X.constants            => 'A'
Y.constants            => 'A'
Z.constants             => 'A'         # Z inherits constants from its 
parent

X::A = 3
Z::A                       => 3           # changes in superclass 
populated to subclasses

Z::A = 4
X::A                      => 3           # changes in subclass remains 
local to subclass

Seems like assignments are made without lookup in superclasses.