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From: Stephen Leake <stephen_leake@stephe-leake.org>
Subject: Re: What is your opinion on Global Objects?
Date: Thu, 20 Nov 2014 10:34:28 -0600
Date: 2014-11-20T10:34:28-06:00	[thread overview]
Message-ID: <8561e9omp7.fsf@stephe-leake.org> (raw)
In-Reply-To: OzTaw.281638$lO7.189293@fx26.iad

Hubert <herrdoktor@fumanchu.com> writes:

> That basically is a vote for global objects. Whether they are accessed
> through a global variable or some sort of getter function that returns
> access, it means bypassing the parameters. Well from what I read here,
> there are no strong opinions for either concept. Strange, I wasn't
> able to find good arguments for or against the two concepts anywhere,

If you can really, truly, absolutely guarrantee that you will _never_
need two different copies of the data structure, then the singleton
pattern makes sense (data in a single variable in a package body).

If you ever need two different copies of the data structure, then you
need to pass it around in parameters.

The symbol table for a compiler is a good candidate for a singleton.

A database connection is not; you will need to copy the database from
one object to another when you change the schema or move to a new
backend in the future.

-- 
-- Stephe


  parent reply	other threads:[~2014-11-20 16:34 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-11-18  1:36 What is your opinion on Global Objects? Hubert
2014-11-18  2:52 ` Jeffrey Carter
2014-11-18  3:08   ` Hubert
2014-11-18  3:16     ` Shark8
2014-11-18  5:09     ` Jeffrey Carter
2014-11-18 11:23     ` Brian Drummond
2014-11-19  2:50       ` Hubert
2014-11-19  3:03         ` Jeffrey Carter
2014-11-19  9:13           ` Hubert
2014-11-19 10:22             ` J-P. Rosen
2014-11-19 17:37             ` Jeffrey Carter
2014-11-20 16:34         ` Stephen Leake [this message]
2014-11-20 21:11           ` Adam Beneschan
2014-11-21 15:25             ` Stephen Leake
2014-11-21 21:53             ` Randy Brukardt
2014-11-21  1:25           ` Hubert
2014-11-21  3:00           ` Brad Moore
2014-11-19 10:11   ` Jacob Sparre Andersen
2014-11-20  6:21     ` Hubert
2014-11-18  8:54 ` Dmitry A. Kazakov
2014-11-20 20:33 ` sbelmont700
2014-11-20 21:35   ` J-P. Rosen
2014-11-21  1:02     ` sbelmont700
2014-11-21  1:31       ` Hubert
2014-11-21  9:01     ` Dmitry A. Kazakov
2014-11-22  7:46       ` J-P. Rosen
2014-11-22  9:02         ` Dmitry A. Kazakov
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