From: "Hal E. Fulton" <hal9000@...>
Date: 2001-12-14T07:21:46+09:00
Subject: [ruby-talk:28466] Re: func_eval?

----- Original Message ----- 
From: Issac Trotts <ITrotts@IdolMinds.com>
To: ruby-talk ML <ruby-talk@ruby-lang.org>
Sent: Thursday, December 13, 2001 4:05 PM
Subject: [ruby-talk:28462] Re: func_eval?


> That's a good thing to know, and it almost answers my question.
> But I still would like to have a way to get the binding of 
> the function that called whichever function is currently 
> executing.

An interesting idea, and it's been discussed before...

One problem I see is that if a method you call can get
your binding *without your knowledge* (I'm personifying
the calling method as "you")... then you can't rely on your
own local variables being unchanged by any method call.

This is contrary to the principle of data hiding, IMO. It's not
that it could be used maliciously, but abused accidentally.
Am I mistaken?

def meth2
  #...
  eval("x=6", caller_binding())
end

def meth1
  x = 5
  meth2
  puts x
end

meth1   # Prints 6 for x!


Hal Fulton