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From: dewarr@my-dejanews.com
Subject: Re: Future Ada language revisions?
Date: 1998/10/05
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In article <3618DAE7.326A@oen.siemens.de>,
  Alfred.Hilscher@oen.siemens.de wrote:
> I have an other question to the Ada95 design: Why does Ada not support
> simple PROCEDURE-Types (like C or Modula). When writing GUI
> applications, one needs always to pass callback routines. They are in
> fact passed as procedure variables. In Ada one have to pass adresses
> instead. While Ada has task type, I did not found any procedure type. Is
> there really none (and if, why not) or am I blind ?


This is a bit peculiar, perhaps you have been looking at an obsolete language
(Ada 83). In Ada 95, there is an access procedure type which does exactly what
you want. Very similar to, but safer than, the use of procedure pointers in C.
This feature was primarily motivated by the need to support callbacks and has
been widely and successfully used for this purpose.

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