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From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: What is your opinion on Global Objects?
Date: Mon, 17 Nov 2014 19:52:49 -0700
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Date: 2014-11-17T19:52:49-07:00
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On 11/17/2014 06:36 PM, Hubert wrote:
> 
> So my question is basically, is it OK to make these entities available through
> global access variables, or should they all be passed as arguments to function
> calls? We all know global objects are bad (not to mention that theorists heftily
> denounce the Singleton Pattern as bad, but, hey there is only one way to the
> internet and only one database, I'm sorry) but we also know that it is bad to
> carry "tramp data" through multiple levels of function calls when the functions
> do nothing with that data but pass it on to lower functions.

This is only a problem in poorly designed languages. In Ada these "singletons"
should be packages. No global variables needed. No access types needed, much
less global access variables.

-- 
Jeff Carter
"So if I understand 'The Matrix Reloaded' correctly, the Matrix is
basically a Microsoft operating system--it runs for a while and
then crashes and reboots. By design, no less. Neo is just a
memory leak that's too hard to fix, so they left him in ... The
users don't complain because they're packed in slush and kept
sedated."
Marin D. Condic
65