Rails - Jul 2007 - Evaluating a variable from it's name

If I have a string variable that contains the "name" of another
variable.  How can I access that other variable for both assignment
and evaluation?

e.g.

x = 100
nameofvar = "x"

I want to set the value of the variable specified by nameofvar and
also get it''s value.

Seems like some sort of reflection calls would be needed for this...


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Hi --

On Mon, 23 Jul 2007, rlaferla wrote:
>
> If I have a string variable that contains the "name" of another
> variable.  How can I access that other variable for both assignment
> and evaluation?
>
> e.g.
>
> x = 100
> nameofvar = "x"
>
> I want to set the value of the variable specified by nameofvar and
> also get it''s value.
>
> Seems like some sort of reflection calls would be needed for this...
There''s eval, but in almost seven years of Ruby program I have never
needed to do that, and would be very surprised if it were really a
good idea.  Anyway, that wasn''t your question, so I''ll leave
it at
that :-)


David

-- 
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Hello,

See the following code:

class Reflection
   attr_accessor :x
   def y
     "y"
   end
   def call_method (method_name)
      self.send(method_name)
   end
end

Now you can do the following things:
>> r = Reflection.new
=> #<Reflection:0xb7172b60>
>> r.call_method("y")
=> "y"
>> r.call_method("x")
=> nil
>> r.x = "test"
=> "test"
>> r.call_method("x")
=> "test"
>>
Best regards,
Jeroen

On Jul 23, 2:24 pm, rlaferla
<robertlafe...-Wuw85uim5zDR7s880joybQ@public.gmane.org>
wrote:
> If I have a string variable that contains the "name" of another
> variable.  How can I access that other variable for both assignment
> and evaluation?
>
> e.g.
>
> x = 100
> nameofvar = "x"
>
> I want to set the value of the variable specified by nameofvar and
> also get it''s value.
>
> Seems like some sort of reflection calls would be needed for this...

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