From: Philip Hallstrom <ruby@...>
Date: 2007-01-12T05:39:52+09:00
Subject: Re: Finding path to ruby script argument

> On 1/11/07, Matthew Hailstone <matthew.hailstone@gmail.com> wrote:
>> Looks like __FILE__ and $0 are the same.
>
> Not necessarily... when running a script under rcov or similar, they
> may differ (for example one starts with ./ while the other does not).
> That's why I write the if __FILE__ == $0 idiom as
>
> if File.expand_path(__FILE__) == File.expand_path($0)
>
> Another possibility might be is when you start the script using $PATH,
> i.e. not from current directory, but without specifying its path.

Also, and i haven't even bothered to test this, but if it's similar to 
PHP's FILE variable, it's the *current* file... so require a file, call a 
method in that file, and access __FILE__ in that method and you're gonna 
get your required file, not the initial one...

-philip