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From: Georg Bauhaus <bauhaus@futureapps.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Running a preprocessor from GPS?
Date: Fri, 31 Jul 2015 09:29:19 +0200
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Date: 2015-07-31T09:29:19+02:00
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On 30.07.15 22:53, EGarrulo wrote:
> By "resource" I mean any resource -- like: database connections,
> files, etc. -- that must be relinquished as soon as possible and that is
> shared among different objects, in a way that makes it difficult for each object
> to determine whether such resource is still needed by other objects or not.  Of
> course, this implies a dynamic environment that precludes the possibility of
> creating all the needed resources in advance and then releasing them at the end
> of computation.

This kind of automatic resource management cannot be real:
How could anything other than the entire collection of objects using
the resource determine whether any one of them still needs the resource?

Therefore, if you have several objects using the resource,
possibly in different tasks, handle the resource with the
help of a protected object.

The protected object implements a protocol. An object wishing
to use the resource will ask the PO for a handle, and will get one ASAP.
In simple cases, the resource can be released by the PO as soon
as all users have signaled to the protected object that they are
done with the resource.