From: Ian Macdonald <ian@...>
Date: 2003-06-04T12:31:28+09:00
Subject: Re: case of sub! not working

On Wed 04 Jun 2003 at 11:38:02 +0900, Yukihiro Matsumoto wrote:

> In message "Re: case of sub! not working"
>     on 03/06/04, Ian Macdonald <ian@caliban.org> writes:
> 
> |In my program, however, I would have been quite happy to have sub! just
> |modify the copy of ENV['PATH'] that it had made, as I wanted to modify
> |the path that would be used to find the location of a binary I was about
> |to open with popen. I wasn't trying to modify the outside environment,
> |just that of my script and any of it children.
> 
> I understand what you feel, but still, environment variables are
> entities in the operating system, the outside world from Ruby.  You
> were trying to modify the environment outside of Ruby, without
> knowing.  Read Hal's explanation again in [ruby-talk:72787].

I understand your reasoning, but why is = any different to sub! ?
If assignment (=) is just a method call with some syntactic sugar thrown
in, then why is it that sub! tries to modify the outside environment,
while = only modifies the singleton copy?

Ian
-- 
Ian Macdonald               | Before borrowing money from a friend,
System Administrator        | decide which you need more.   -- Addison H.
ian@caliban.org             | Hallock 
http://www.caliban.org      | 
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