From: Ken Bloom <kbloom@...>
Date: 2008-04-04T22:40:16+09:00
Subject: Re: Using a string as executable code

On Thu, 03 Apr 2008 20:42:28 -0500, Paul McMahon wrote:

> Peter Marks wrote:
>> I need to store one line method calls as strings in my db and then
>> apply them to an object. For example, I would store "name.upcase" in
>> the db and then somehow call person.name.upcase. Any idea how I might
>> pull this off?
> 
> Well, you could do
> 
> result = "name.upcase".split(".").inject(person) do |object, method|
>    object.send(method)
> end
> 
> but storing code in a database smells.  Perhaps it would be better to
> find another approach that avoids storing the code in the first place

Your answer also smells. I'd use instance_eval.

result = person.instance_eval "name.upcase"

--Ken

-- 
Ken (Chanoch) Bloom. PhD candidate. Linguistic Cognition Laboratory.
Department of Computer Science. Illinois Institute of Technology.
http://www.iit.edu/~kbloom1/