Re: Distributed Systems Annex, data sharing between programs

[Adam Beneschan <adam@irvine.com>]

On Tuesday, June 5, 2012 12:36:01 AM UTC-7, Maciej Sobczak wrote:

> > If my understanding is correct, my next question is: is there any language-defined support for sharing data between programs
> 
> Do you expect it to be language-defined? Why? Ada is not the only
> language (not even the only ISO-stamped one) and heterogeneity is a
> natural property of systems composed of multiple programs. Defining
> data sharing between programs written in the same language would be a
> wasted effort (better spent elsewhere in the standard). Instead, allow
> others (third-parties) to define it so that programs written in
> different languages will be able to share data - this will have much
> bigger benefits.

My reasoning here is that the DSA requires mechanisms to pass objects of Ada types between partitions (of the same program?) transparently, and also to share data in Shared_Passive partitions transparently, without users having to worry about the representation.  So it would seem like a natural extension to provide this sort of communication between "programs".  The mechanisms would already exist.  On the other hand, you have a point that writing a server that uses a feature like this would limit the programs that could use the service to those written in Ada.  I still think this would be useful in some situations--for example, if the server and clients were expected to be used within one company (or one division of a company), so that it might be reasonable to expect that all programs be written in a common language.

                              -- Adam