From: Ryan Davis <ryand-ruby@...>
Date: 2007-07-03T05:47:07+09:00
Subject: Re: getting rid of $0


On Jul 2, 2007, at 11:11 , Alex Young wrote:

> Tim Pease wrote:
>> On 7/2/07, Michel Demazure <michel@demazure.com> wrote:
>>> The common idiom
>>>  if __FILE__ == $0 then ...
>>> gives bugs when $0 is not what one would expect, for instance  
>>> under a
>>> debugger, or in rubyscript2exe, etc.
>> require 'English'
>> if __FILE__ == $PROGRAM_NAME
> Does that solve the problem?  Isn't that vulnerable to the same  
> issues as just using $0?

Solve what problem? The code is doing what you asked it to do, that  
isn't a problem, that's programming.

The code clearly reads "if this file is the program" which is NOT the  
case when run under a debugger. I'm not sure what rubyscript2exe  
generates, but my guess is that can be solved on their end somehow. I  
generally don't want that code to run when I'm poking around in a  
debugger or something similar. If I do, I set the values inside the  
debugger and don't worry about it.