From: Robert Klemme <shortcutter@...>
Date: 2009-03-03T02:13:57+09:00
Subject: Re: What does this statement do?

On 02.03.2009 15:27, Jason Roelofs wrote:
> On Mon, Mar 2, 2009 at 9:18 AM, Stanislaw Wozniak <stan@wozniak.com> wrote:
>> Stanislaw Wozniak wrote:
>>> Hi Guys,
>>>
>>> I have been wondering what does this statement do and what does it set.
>>> It interferes with my methods_missing handler:
>>>
>>> {code}
>>> class MyClass
>>>
>>>    something = "something else"
>>>
>>> end
>>> {code}
>> I guess this is assigning a string to a variable that is created in the
>> MyClass scope. But my problem is that I have some setter methods that
>> I'm using through method_missing, but method_missing is never triggered
>> because it is assigning stuff just like in the example above.
>> --
>> Posted via http://www.ruby-forum.com/.
>>
>>
> 
> That statement is the same as calling MyClass.something=("something else")

Actually, no.  See Rick's excellent explanation.  For test addicts:

[oracle@ora01 ~]$ ruby y.rb
test 1
foo called with 123
test 2
[oracle@ora01 ~]$ cat y.rb

class X
   def self.foo=(a)
     printf "foo called with %p\n", a
   end
end

puts "test 1"
X.foo = 123

class X
   puts "test 2"
   foo = 987
end

[oracle@ora01 ~]$

> If you want method_missing to catch it, you need to define a
> method_missing on the class itself, like this:
> 
> class MyClass
> 
>   def self.method_missing(name, *args)
>   end
> 
> end

Won't help here, because the statement is interpreted as a local 
variable assignment.

Kind regards

	robert