how private is private in ruby? - comp.lang.ruby

Message from discussion how private is private in ruby?
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From: Edward Faulkner <e...@alum.mit.edu>
Newsgroups: comp.lang.ruby
Subject: Re: how private is private in ruby?
Date: Thu, 27 Oct 2005 04:45:40 +0900
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On Thu, Oct 27, 2005 at 04:32:36AM +0900, Peter Ertl wrote:
> Why is this allowed / possible?
> $ puts ks.send(:key)
>
> so I can just use [public] for _everything_ as well, right?

While it may or may not be a good idea that #send subverts access
control, your choice of example betrays a misunderstanding of the
meaning of "private".

"private" is not intended as a security measure.  It's an
encapsulation technique.  You'll find this is generally true in other
languages as well.  You can certainly subvert "private" in C++.

"private" exists only to tell other programmers which methods they
really shouldn't be calling. =20

regards,
Ed

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