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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Safety of unprotected concurrent operations on constant objects
Date: Tue, 13 May 2014 17:46:58 +0100
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Date: 2014-05-13T17:46:58+01:00
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Brad Moore <brad.moore@shaw.ca> writes:

> That may be why Ada has PO's in the standard, but does not provide any
> mutex libraries like the one you suggest; They are too error
> prone. I'd be surprised if mutexes and scope locks like the one in
> your example wouldn't have been considered for inclusion in the
> standard at some point during the history of Ada.  Ada does provide
> the building blocks that programmers can create such abstractions
> however, which programmers are then free to use as they wish.

I've several times seen Randy recommend use of the Containers as a way
of avoiding problems with memory allocation/deallocation, and I'd have
thought simple mutexes/locks would be just as much candidates to support
the general user.

Are they error-prone? If Joe Programmer reinvents locking, what's the
chance that there's something wrong with it?