From: Steve Hull <p.witty@...>
Date: 2009-06-02T09:12:31+09:00
Subject: Re: eval?  instance_eval??  hmm

James -- perfect.  Thanks!

Brian Candler wrote:
> You can easily see what you've done wrong if you just use 'puts' instead 
> of 'myObject.instance_eval'
> 
> Here's it's because you turned the hash into a string, and then inserted 
> the string into your code, and then tried to run it.

Believe it or not, I did realize that.  I just couldn't find any docs 
showing me the proper usage of the string form of "instance_eval" (ie, 
passing an argument).

> irb(main):005:0> instance_eval "#{myMethodName}(myHash)"
> got {"one"=>1}
> => nil

See I thought about trying this, but didn't even bother, as I expected 
it to fail.  Anyway I'm glad to see it does indeed work like this.

> However there are better ways to achieve this, without using the string 
> version of eval. Probably all you want is this:
> 
>     myObject.send(myMethodName, myHash)

Yup.  This works perfectly, thanks!!

> This isn't metaprogramming (metaprogramming = programs which write 
> programs). This is just dynamic method dispatch.

Hah yeah I realize that now...  cut me some slack, it was ~1:30am my 
time and the wife was harassing me to come to bed!  ;)
Anyway, as you may have guessed, I'm new to Ruby in general.  Only been 
working with the language for about 3 months.  So far I'm loooooving it. 
:)

Thanks for the helpful replies!  I got it working exactly how I wanted.

-Steve
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