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From: Jacob Sparre Andersen <jacob@jacob-sparre.dk>
Newsgroups: comp.lang.ada
Subject: Re: Community Input for the Maintenance and Revision of the Ada
 Programming Language
Date: Fri, 01 Sep 2017 19:53:33 +0200
Organization: JSA Research & Innovation
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Date: 2017-09-01T19:53:33+02:00
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Björn Lundin wrote:

> I sometimes find the need to auto generate code from some kind of
> description.
> It would help quite a bit if there was a way to
> * iterate over fields in a record
> * query a field of its properties, like type, length if applicable

One option, as Jean-Pierre suggests, is to write a suitable tool using
ASIS.

Another option is to make your Data_Type type implement a "Visitor"
interface, and go that way.

I would usually suggest writing an ASIS-based tool, but I can easily
find a champion for using the "Visitor" pattern as well.

Greetings,

Jacob
-- 
»A corollary of Murphy's law is that duplicate information
 eventually becomes different information.  Putting both in
 the same file may slow down the process, but it will not
 prevent it.«                                 -- Wes Groleau