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From: Rein Henrichs on 5 Jun 2010 20:13
On 2010-06-05 17:02:17 -0700, Joel VanderWerf said:

> Anyway, attr_accessor is already a private module method in ruby, but
> the instance methods it creates are not, by default.

I stand corrected. Interesting.

--
Rein Henrichs
http://puppetlabs.com
http://reinh.com

From: Luis Lavena on 5 Jun 2010 20:33
On Jun 5, 6:25 pm, Joel VanderWerf <joelvanderw...(a)gmail.com> wrote:
> Consider this error:
>
> $ cat t.rb
> module M
>    private
>    def attr_accessor(*args); super; end
> end
>
> class C
>    extend M
>    attr_accessor :x
> end
>
> C.new.x = 1
>
> $ ruby19 t.rb
> t.rb:11:in `<main>': private method `x=' called for
> #<C:0x0000000091c670> (NoMethodError)
>
> That looks very suspect, so I was about to file a bug report. But then I
> noticed that there is a warning reported with the -v switch:
>
> $ ruby19 -v t.rb
> ruby 1.9.2dev (2010-05-31) [x86_64-linux]
> t.rb:3: warning: private attribute?
> t.rb:11:in `<main>': private method `x=' called for
> #<C:0x000000012e5670> (NoMethodError)
>
> Does anyone understand this warning? Is 'private' (without an argument)
> deprecated?

Maybe is because you're setting private for all the following methods,
including the ones that attr_accessor defines moving forward after the
"extending"?

if you change the private to 'private :attr_accessor' there is no
warning and things works.

--
Luis Lavena
From: Joel VanderWerf on 5 Jun 2010 20:48
Luis Lavena wrote:
> On Jun 5, 6:25 pm, Joel VanderWerf <joelvanderw...(a)gmail.com> wrote:
>> Consider this error:
>>
>> $ cat t.rb
>> module M
>> private
>> def attr_accessor(*args); super; end
>> end
>>
>> class C
>> extend M
>> attr_accessor :x
>> end
>>
>> C.new.x = 1
>>
>> $ ruby19 t.rb
>> t.rb:11:in `<main>': private method `x=' called for
>> #<C:0x0000000091c670> (NoMethodError)
>>
>> That looks very suspect, so I was about to file a bug report. But then I
>> noticed that there is a warning reported with the -v switch:
>>
>> $ ruby19 -v t.rb
>> ruby 1.9.2dev (2010-05-31) [x86_64-linux]
>> t.rb:3: warning: private attribute?
>> t.rb:11:in `<main>': private method `x=' called for
>> #<C:0x000000012e5670> (NoMethodError)
>>
>> Does anyone understand this warning? Is 'private' (without an argument)
>> deprecated?
>
> Maybe is because you're setting private for all the following methods,
> including the ones that attr_accessor defines moving forward after the
> "extending"?
>
> if you change the private to 'private :attr_accessor' there is no
> warning and things works.

True. However:

$ cat t.rb
module M
private
def attr_accessor(*args); super; end
public # <-- added this line
end

class C
extend M
attr_accessor :x
end

C.new.x = 1

$ ruby t.rb
$ ruby19 t.rb
t.rb:12:in `<main>': private method `x=' called for
#<C:0x00000001e40858> (NoMethodError)


From: Joel VanderWerf on 5 Jun 2010 21:06
Luis Lavena wrote:
> Maybe is because you're setting private for all the following methods,
> including the ones that attr_accessor defines moving forward after the
> "extending"?

That's probably true in some sense (some state is getting set and
affecting the methods defined by attr_accessor), but it's not setting
other methods private:

$ cat t.rb
module M
private
def attr_accessor(*args); super; end
end

class C
extend M
def m; puts "m"; end
attr_accessor :x
end

C.new.m
C.new.x = 1

$ ruby19 t.rb
m
t.rb:13:in `<main>': private method `x=' called for
#<C:0x00000002442148> (NoMethodError)


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